Hi

Do you have a link to a video you can share where this is happening?

Do you have any add-ons installed in Firefox?

Welcome to Hncarey: This issue usually happens because of Firefox’s audio initialization delay with some Bluetooth audio drivers — especially when Windows puts the audio device in a low-power state until sound starts.

✅ Try These Fixes:

Disable “Bluetooth Audio Power Management” in Windows

Open Device Manager → Bluetooth → your headset device → Properties → Power Management tab

Uncheck “Allow the computer to turn off this device to save power.”

Restart your PC.

Change Firefox Audio Settings

In Firefox address bar, type:

about:config

Search for:

media.setsinkid.enabled

and make sure it’s true.

Also search for:

media.cubeb.output_voice_routing

and set it to false.

Restart Firefox.

Update or Re-pair Bluetooth Headset

Remove the device from Bluetooth Settings → Devices → Remove device, then reconnect.

Update your Bluetooth and sound drivers via Windows Update or your PC manufacturer’s site.

Optional workaround

Play a short silent audio clip (or keep a silent tab open) — this keeps the Bluetooth channel “awake,” preventing fade-in.

🎧 Why it happens: Firefox initializes the audio stream a fraction of a second later than Edge, and some Bluetooth devices fade in the first second of audio when waking up from idle mode.