Random audio drops when using optical

For reference I’m using a Fiiok11 and for some odd reason when I’m in game, maybe every 1-2 minutes, the audio randomly goes noticeably quieter, makes a clicking sound then back to normal. I’ve checked and I’m not hammering the disc or CPU so I have no idea? Might it be a driver issue? I’ve tested on usb C and all good. The amp only has one usb C port so I’m not a fan of having to keep unplugging it for different devices