I recently bought a refurbished Denon AVR-485 receiver. Off late, I have been getting a very low sound signal from the center channel speaker. I am feeding the receiver the digital audio signal through the coax output from the DVD player. The receiver displays the correct Dolby Digital message on the display as it should. However, the center channel or dialogue sounds muted, compared to the other channels.
I have reset the receiver twice now and the problem persists. The sound initially is okay but then the volume from the center channel starts to deteriorate. I have also replaced the center channel speaker with one of my bookshelf speakers and I get the same problem. I have checked the speaker polarity as well. I will be calling Denon tech service but the product is outside its 90 day warranty period (it is a B stock), so repairing the unit may not make sense from a cost point of view.
Has any one of you faced this problem? What else could I possibly do at this stage? How about measuring the DC output at the speaker terminals? Would that tell me anything?
Is it possible to assign the center channel speaker output to the zone B speaker terminal or the surround back output?
I am new to AV receivers and would appreciate any help.
Thanks a lot, blueberry p.s: This experience is making me rethink buying refurnished units.
If there were DC at the speaker terminals, the center channel speaker probably wouldn't be working at all. So there's not much point in measuring that parameter. As far as the analog portion of the amplifier goes, there isn't much reason the center channel amplifier should fade away in output. This indicates the problem is probably in the digital section. A front center channel is just that and nothing more or less, it cannot be reassigned to the other terminals without degrading the surround system.