left audio output R10 loud buzzing

Our receiver is 5+ years,and have had the connections set up untouched for over 3 years, and it appears the left audio output connector on the receiver stopped working as it has a loud buzz (this has been constant for about 2 months).  We have it going to the DVD player/recorder, then the surround sound, and have determined the right output connector is still working. I've changed the cables, switched the connections (meaning I went from right output to left input on the DVD and it works, just changes the speaker the sound comes out of, it only creates a buzz whenever the left audio output is being used/plugged in). We've gotten around it for the past 2 months by watching TV using the direct cable from Tivo to TV on channel 3, but we'd like to use our surround sound.  We can watch DVDs with no sound or audio problems, we just change it to input 1 (which is what we used to keep it on all the time until the buzzing started). 

We're thinking our receiver is just old and needs replacing.