Get out the manual and read the troubleshooting section. Look on the back of your receiver for something that looks like a screw cap, that may comtain a fuse. There could also be a breaker and a reset button. If it has an A/B speaker switch, try the B terminals. Try the speakers in the rear terminals to make sure they work etc..
I have an old TEAC AG-8900 receiver and the sound has stopped from the front speakers. I have tried different speakers and changed the speaker wire to no effect. Because of the expense, I can't bring it in for service so I was wondering if anyone could suggest what I might to myself to correct or troubleshoot this. I read online that some receivers have seperate fuses for different speaker sets, for instance. Any idea where these might be located? I'd greatly appreciate any other suggestions. Thanks very much.