Headset issue unable to speak but can hear all audio.

Not enough information are you using a headset if so what audio cable come with it 3.55mm jacks? optical audio cable? can you hear them speaking?

What type of headset are you using? Can you hear game audio trough this headset and the issue is only while playing videos? or you hear always only chat?

I'm having a very similar issue. For whatever reason game audio isn't coming through entirely. Like in PUBG I can hear other people walk, but not myself. When I'm driving I can kind of hear the car, but it's almost like I'm hearing it from a distance.
For the Arkham games I can hear Batman's internal dialogue, but no one else speaking. The same thing occurs regardless of the headset or controller.

Hello,

You'll need to give a little bit more information than that. Is this a wired headset or a wireless headset? Have you tried plugging the headset into a different controller to see if that fixes the issue?

Have you looked to see if the headsets mute button isn't pushed? (That's the most common issue in situations like this).

Have you checked your preferences to make sure that everything is set correctly? You can do that by pushing the middle button on your Xbox 360 Controller and going to Settings > Preferences > Voice > Make sure that the settings in there along with the volume
sliders are up.

Hopefully I can offer some help. Can you not hear any audio through the headset at all? And have you checked the volume control on the headset?