I have to turn the avr 7200 way up to get somewhats of a loud responce, but when there is no music, i hear a hsising noise. I never used this reciever in 10 years. what could it be?
Unless permanent hearing damage and the destruction of your equipment is a goal, NEVER USE MAXIMUM VOLUME FOR TROUBLESHOOTING or any purpose.
Turn the volume control to something medium.
The errant switch, control or condition may change and you will suddenly release the amp's full power and possibly destroying your speakers. If a signal isn't audible at 1/2 volume it's probably not there.
Carefully examine the front panel for clues like a misplaced Source Selection, Mute, Tape Monitor control or Multichannel Analog Input selected.
There is a good chance that a common control may have developed a high-resistance or 'dead' spot through defect or idleness and is causing your symptom. Turn the POWER OFF and operate every control throughout its range a number of times, especially rarely-used ones like Tape Monitors and the Mute control.
Turn the volume to something reasonable and see if that helped.