Not that I know of. The volume control on the television set will amplify the speakers in the television, but the fixed output is designed to send a fixed signal to an amplifier. Many systems have an AUX input, where the volume can be adjusted on the HT unit itself (and with the remote control, if applicable). Does that not work?
I bought a 7100 series TV. I want to connect it to a 10 yr old lifestyle bose system from the fixed miniplug output. IS THERE A DEVICE I can use to vary the sound output to the
bose system which is set up to require the input to be variable.