Firefox Community Forum

Hello All,

I have a somewhat confusing issue that I've only found two posts on Reddit mentioning previously, but there were no responses.

A short summary: On Discord's website, in an audio call, audio will progressively move from stereo/both ears to mono/only the right ear after anywhere from five to sixty seconds. This only occurs on Firefox, it does not occur on Chrome or Edge (with the same extensions, when applicable.) For the record - this also only occurs with the one headset. I've tried with a second headset and don't have the same issue, but I don't believe the Headset is solely to blame since the issue only happens on Firefox.

I have also tested on Firefox Nightly as a fresh install - no extensions, no settings changed, just install and login to Discord.

Specs:

ASUS TUF Dash F15 FX517ZR HP USB-C G5 Essential Dock (Monitors are connected through it) Windows 11 (August update/build 26200.9168) Razer Blackshark V2 Pro RZ04-0453 headset (Connects via USB-A Dongle plugged in to the laptop) Firefox (x64) (154.0.1)

Troubleshooting steps I've taken:

Removing the Audio driver for my computer and re-installing it. Removing/re-installing the drivers for the Headset. Verified all audio related drivers for my device are up to date. Verified the BIOS is up to date (it's solved unusual problems before) Toggling the "media.latency_preference" toggle in about:config (recommendation from a friend) Disabling all extensions on Discord. Disabling Firefox's strict mode on Discord. Verifying all audio related drivers for my device are up to date. Tested on a Firefox Nightly install (the first time it's been installed on my device). A separate browser (Chrome/Edge - the issue is not present) A separate headset (Issue is not present) Downloading Razer Synapse and disabling any "extra" features, and testing with various options on/off. Disabling any and all other Audio devices (speakers and microphones) while using the headset. Charging the Headset to full.

Things I haven't tested, but thought of:

Resetting Firefox in any capacity - I can, but hopefully testing with Nightly is sufficient. A different computer entirely - on my list, when I can next. A new User profile. Testing with no headset at all, and just utilizing the built-in speakers/microphone for the laptop.

Oddities:

Changing audio settings in Windows will "fix" the issue momentarily - for instance the "Spatial sound" option. Changing from one setting to "Off" (or vice versa) fixes the issue for the same ~5-60 seconds until it slowly goes back to the right ear. These options are present for every device, even ones not experiencing this issue.

It's very odd to me because on one hand it may be the headset, but then the issue is only present in Firefox.

Any help or things to test would be greatly appreciated!

Thank you.

[Audio Issue] Firefox Causes Background App Volume Drop on Tab Focus — All Volumes at 100%, Issue Not Present in Portable

Issue Summary: Whenever I focus a Firefox tab (even a blank or safe mode one), the audio volume of background applications (e.g., Spotify) drops or changes audibly. It’s not a ducking effect (as all ducking settings are disabled), and Windows volume mixer shows all apps still at 100%. The issue happens only while Firefox is focused — not minimized, not unfocused.

Reproduction Steps:

Play music using Spotify or another app.

Focus any Firefox window or tab.

Background audio becomes quieter or altered — then returns to normal once Firefox is unfocused. Specifically on focus it will change system volume to 58, then return to what it was previously when unfocused.

System Info:

OS: Windows 11 (fully updated)

Firefox Version: 128.0.2 (issue present since at least 127)

Audio Output: Realtek and NVIDIA High Definition Audio (same issue on both)

Spotify Version: Latest Windows Store version

Windows Sound Settings:

Communications tab: "Do nothing"

All app volumes: 100%

No enhancements or spatial effects enabled

Troubleshooting Already Tried (No Success):

Step Result ✅ Disabled audio ducking in Windows No effect ✅ Disabled audio enhancements No effect ✅ Ran Firefox in Troubleshoot Mode (Safe Mode) Issue persists ✅ Changed Firefox audio backend to winmm via about:config No improvement ✅ Fully reset Firefox profile (about:support → Refresh) Issue persists ✅ Verified with Process Explorer (audiodg.exe shows activity on tab focus) Confirms session change ✅ Ensured all apps in volume mixer show 100% No volume mismatch ✅ Rebooted and tested cleanly Still occurs ✅ Tested Firefox Portable (fresh instance) Issue does NOT occur (portable version behaves as expected)

Additional Notes:

The issue appears to be triggered by the main installed version of Firefox only.

A completely clean portable version does not cause the volume change, suggesting something related to the system-wide install, global config, or registry entries is affecting it.

Even without extensions, without playing any video/audio in Firefox, just focusing the window causes this volume behavior.

What I Plan to Try Next:

Fully uninstall Firefox (including deleting AppData and registry leftovers), then reinstall cleanly to see if that resolves it.

Possibly test Firefox ESR if needed.

Request for Help:

Has anyone experienced Firefox causing audio session or DSP changes on focus, especially with audiodg.exe activity?

Could there be a hidden system-level or registry config that ties Firefox to a shared exclusive audio session?

Any way to trace which audio sessions Firefox creates and how Windows handles them?

Let me know if you'd like logs, about:support data, Process Explorer thread captures, or a video of the issue. I’d appreciate any help from the community in narrowing this down.

Thanks! —Justin

No sound, thought speakers went bad. Bought a microphone and still no sound. How do I do Doxy.Me or Zoom without outgoing sound?

Context

While playing YouTube videos in Firefox, intermittent crackling appears after a few minutes of playback. This report documents detailed testing that demonstrates the issue is not related to the DAC, USB interface, or system hardware, and is exclusive to Firefox.

2. System Configuration

CPU: AMD Ryzen 5 5600X @ 43 °C

RAM: 64 GB DDR4 dual-channel (16-20-20-38 @ 1572 MHz)

Motherboard: ASRock X570 Phantom Gaming 4 (AM4) @ 54 °C

GPU: NVIDIA GeForce RTX 3050 (audio drivers disabled, audio hardware off)

Monitors: LG HDR WFHD 2560x1080@60Hz and IPS236 1920x1080@60Hz

Storage: Multiple SSD and HDD SATA drives (500 GB – 2 TB)

Audio: Realtek High Definition Audio disabled; iFi nano/UNO DAC connected via USB with power filtering, using Exclusive Mode / ASIO

3. Tests Performed 3.1 DAC and USB Validation

Continuous playback of PCM 384 kHz/24‑bit and DSD256 via Roon/ASIO.

Duration: over 25 minutes of uninterrupted DSD256 playback.

Result: no crackling, pops, or errors.

Conclusion: DAC, firmware, USB cables, ports, and power supply are fully operational; heavy data load does not cause errors.

3.2 Browser Comparison

Chrome (YouTube, identical conditions): continuous playback without crackling.

Firefox (YouTube, identical conditions): crackling progressively appears minutes into playback, temporarily disappearing when the video is paused.

3.3 Isolation of Variables

USB motherboard ports and original drivers fully tested.

GPU audio drivers and hardware disabled.

Windows Shared Mode off, Exclusive Mode enabled.

Predefined audio formats set according to DAC preferences.

USB power management disabled.

DAC temperature stable; no overheating observed.

4. Technical Conclusion

Hardware: DAC, USB, cables, power, firmware, and GPU are not the cause of the crackling.

Operating System: Windows 11 is correctly configured; Exclusive Mode / ASIO works without errors.

Browser: Firefox is the only element consistently reproducing the issue.

Most Likely Cause: Firefox’s buffer management and audio sandboxing interacting with Windows, causing intermittent interruptions in audio flow.

Summary: All hardware and OS factors have been tested and validated: DAC, USB, cables, power supply, firmware, GPU, and temperature do not produce crackling. The only consistent factor is Firefox, making this a software-bound issue.

Engineering Note: This diagnosis conclusively demonstrates that the intermittent audio crackling on YouTube is caused exclusively by Firefox on Windows 11, independent of DAC or USB hardware. The issue should be investigated at the browser level, specifically how Firefox handles continuous digital audio streams and buffers on Windows.

Issue Description: I’m experiencing a problem with fullscreen mode while using YouTube on Firefox on Windows 11 with a dual-monitor setup. When I enter fullscreen, the video does not cover the entire screen. Instead, I can still see parts of the Windows desktop or background around the edges of the display.

This issue only happens on Firefox and only when using fullscreen mode on one of my monitors. I have already checked my display settings, scaling, alignment, and hardware acceleration, but the problem persists.

System Details:

Windows 11

Dual-monitor setup

Browser: Firefox (latest version)

Issue: Fullscreen video shows borders and does not fully cover the screen

Expected Behavior: The fullscreen video should completely fill the selected monitor without showing any part of the Windows desktop.

Please advise on how to resolve this issue.

subtitles appearing on all YouTube content, even though subtitles turned off. I have toggled the cc button and also subtitles in settings with no luck. The cc box does work to turn subtitles in not YouTube videos.

Hello Firefox Support,

I’m encountering a strange issue with Firefox. While playing YouTube videos at very low quality (144p) just to listen to music, my GPU usage spikes to 100%. This happens even when the video is not fullscreen and there’s minimal visual content.

System Info:

   Firefox Version: 140.0.2 (64-bit)

   Operating System: Windows 11 

   CPU: AMD Ryzen 7 8700F (no integrated GPU)

   GPU: AMD Radeon RX 7900 GRE

   GPU Driver Version: AMD Adrenalin 25.6.1 

The issue goes away when I disable hardware acceleration in Firefox settings, but I’d prefer to leave it enabled for better performance elsewhere.

Is this a known issue with AMD GPUs or is there something else I can try to reduce GPU usage during playback?

Thank you for your help.

why do videos opened in new tabs have an audio delay before the sound comes on? this is a recent phenomenon. So, when I right click a video and click 'open in new tab' when the video starts the audio is delayed 2 to 3 seconds. normally there is no audio lag. this has been happening for perhaps two weeks now. is it related to a setting? I recently adjusted the security and privacy settings.

Hi. Every time I go into youtube, the sound cuts out after about an hour. I then have to go to settings, volume mixer and Mozilla Firefox and click on the X to get the sound back. Youtube has assured me this is not their problem, but a Mozilla one. I've been with Firefox for many many years and have never had this problem. Could you please advise me as to what to do about this ? Thank you.

It seems to be related to video playback but not sure. It was happening while a video was playing full screen, and also after stopping playing/hiding a non-full-screen video.

To catch the issue had to screen record at 240fps. I used Nvidia Overlay to record the issue, but was happening before the overlay was even enabled.

Disabled all addons, made no difference. HW acceleration on or off, still happened.

I tried turning on logs, and this always seemed to show up with the flash: ``` 2026-08-09 06:19:44.048000 UTC - [Parent 8388: Main Thread]: D/Widget GetWorkspaceId - calling AsyncUpdateWorkspaceID() 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget calling GetWindowDesktopId 2026-08-09 06:19:44.048000 UTC - [Parent 8388: Main Thread]: D/Widget GetWorkspaceId - calling AsyncUpdateWorkspaceID() 2026-08-09 06:19:44.048000 UTC - [Parent 8388: Main Thread]: D/Widget GetWorkspaceId - calling AsyncUpdateWorkspaceID() 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget called GetWindowDesktopId, hr=00000000 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget calling GetWindowDesktopId 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget called GetWindowDesktopId, hr=00000000 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget calling GetWindowDesktopId 2026-08-09 06:19:44.048000 UTC - [Parent 8388: BackgroundThreadPool #276]: D/Widget called GetWindowDesktopId, hr=00000000 ```

When I watch Downton Abbey on PBS from outside the U.S, using the Firefox VPN in a Private Window the Closed Captions of the PBS video are displayed TWICE: one above the timeline and the other above it.

This issue is specific to this particular show AND to the Firefox browser.

I cannot play embedded Youtube videos, but they work when I open them in Youtube.

When embedded, after starting the video, I only see the circle animation (loading), but the video never starts.

Example: https://telex.hu/video/2025/07/30/gazdagret-plebania-katolikus-egyhaz-lidl-zoldterulet-lakossagi-forum

What I tried so far: 1. turning off hardware acceleration 2. private window 3. troubleshoot mode

The issue has been going on since a long time already, and present on both Windows and Linux Ubuntu.