Original post by: oldturkey03 ,
if you have no difference on your balance settings, I would go ahead and take a look at the AN7470 Stereo decoder as well as the IC NJM45580-x. Of course you also should look for any burned out components on the logic board. Download the service manual for your Onkyo [http://www.archive.org/download/OnkyoTx-800ServiceManual/OnkyoTx-800ServiceManual.pdf|from here.] It does have the circuit diagram as well as a parts list that will help you with it.