Idon't have sound

Hi aslaman, Does Firefox have sound on other websites, or is YouTube the only site where there is no sound? If other websites also have no sound, first check that Firefox isn't muted in your computer's volume mixer while a video is playing. Mozilla also recommends checking that your speakers or headphones are connected and working in other applications. If sound works normally elsewhere in Firefox but not on YouTube, could you let us know your Firefox version and operating system? Also, does the same YouTube video have sound in another browser? That will help determine whether this is a Firefox-wide audio problem or something specific to YouTube.