Re: TV volume from home theater system
You must have used the audio output from the TV to feed the audio system? If so, you will need to turn off the internal TV speakers and either set the audio output to fixed rather than variable or put the volume all the way up. Then use the sound system remote for volume control.
When using the internal speakers there is not enough signal going out of the TV unless you turn the volume on the TV all the way up. Some people put an amplifier between the TV and the sound system to get around this limitation.
Another option would be to connect the audio from your source to the sound system. And use the sound system remote for volume.