[Just Cause Sound Glitch Issue]

So, I FTPed Just Cause to my Xbox a while back, and I get audio during the main menu upon bootup, and audio during the first cutscene, but as soon as gameplay starts, the audio stops working. It's not my A/V cables because I know they're all the way in, otherwise the sound wouldn't play, nor is it the settings in-game. Any ideas on what could be causing this sound glitch? I should add, it's only Just Cause that has this issue, not my other games.

[Hey]

Hey everyone, Scott's on the forum now, but I'm not new to the group on Facebook.