I have a 15 RG and when using the usb/thumb drive I'm not able to advance or go back with the volume control stick. It was working fine the other day, then not. Nothing was changed or unplugged when this happened. I have 1.18.3 version of software, and the latest version has no mention of this problem as a fix.

What can I do to fix this?

Thanks

 

I found what was causing the problem. In the menu screen make sure its set to SEEK, not SCAN. Don't know how it changed over night but that's what fixed it.

 

Yes that! Happened to me a few weeks ago. Came here and asked the same question. That answer is the fix!