Pressing media keys on a keyboard (mute/volume/skip/play/pause etc) will also send a corresponding letter key to UIS.
Mute > D
Volume Down > C
Volume Up > B
Previous Track > Q
Play/Pause > G
Next Track > P
Happens all the time, and while I don’t play very many games, two of the games I do play have actions bound to C and G and pressing the corresponding media button above will trigger those actions: Bee Swarm Simulator Phantom Forces
Not entirely sure when this started happening, lowering my volume has caused me to crouch in phantom forces for as long as I can remember.
This still happens, When playing roblox and turning down my volume or increasing it, It triggers the keys stated in the initial post. Holding mute makes me move to the right. I wonder why it still does it. Its been 2 years since this was initially reported.