I have a good condition Yamaha DSP-A1000 which I use all the time, for all sorts of reasons ranging from TV to Brawling on the Wii. Now I seem to have a bit of a problem. Recently, the sound has started coming through crackled, to not at all for some if not all channels. I have 5 speakers hooker up to it, not counting the subwoofer. It can sometime be fixed by tapping on the top of the unit. It can sometimes restore the sound, but will almost never restore the sound completely. It also appears that it tends to go away from time to time, only to come back when I go to something quiet on TV. It was working very well when I first got it, so any ideas on what it might be and how to fix it?
Note, it's an old unit that used to belong to the family, but when we moved, didn't have a place to put it, and I wanted it, so he gave it to me.
Note, it's an old unit that used to belong to the family, but when we moved, didn't have a place to put it, and I wanted it, so he gave it to me.

