I use the Cinergy in the Car normally.. there's no issues with the Sound level, and it doesn't change when going into TV either. This may be an issue between the TV plugin and the sound card drivers -- There's nothing in RR that will modify/set volumes while in TV... I believe CDRSkull has reported the same issue (with a different tv card!) which leads me to believe it doesn't have to do with the Cinergy 600 itself. I'd recommend playing around with the TV plugin's settings and perhaps trying a different version. it is most likely that if you simply start the TV plugin OUTSIDE RR it will still come up with the same issue -- I suggest you verify it.