I am facing "no sound" problem with a new Denon receiver AVR-X3500H. There is no sound from any speaker at all. If I start audyssey setup, and at minimum complete first speaker test which is subwoofer level check, then everything works fine as long as it remains ON. The moment I put it in standby or switch off the power supply, then same problem occurs when I switch it ON next time. In other words, I have to perform audyssey setup (till subwoofer level test, at minimum) *every time I power it ON*, otherwise there is no sound. This is irrespective of which input or type (HDMI, digital, analog, auto) I select, and no settings other than audyssey setup can bring back sound. Completing audyssey setup doesn't solve the problem either. Irony is that most of it's 3 years warranty period is still available, but I can't claim it because it was bought in another country (USA). I tried all sorts of resets and firmware updates to no avail. Even took the unit to a local Denon service center, where they tried some s/w upgrades, but that didn't help either. I guess all they did was firmware updates that I had already tried at home. They said main/digital/HDMI board has to be replaced, which is quite costly!
That is compelling me to try out some component level diagnosis and fixing if possible. I can take some chances in case I have to change the main board anyway. So, caught hold of a copy of service manual for this model from here:
and did some troubleshooting based on that. After looking into all schematics and symptoms of the problem, I suspected that a signal named MVOL_MUTE driven by the CPU chip to INPUT board is somehow not getting set to high in the beginning after power on (high=unmute, low=mute), and audyssey setup somehow brings it back. I traced it on boards and checked with a multi-meter, and it is indeed confirmed. The concerned signal remains low in the beginning, but it is set to high (3-4V) once I perform audyssey setup and then everything starts working fine. Note that this signal is not used for muting when I press mute button on the remote. It remains high both in muted and unmuted conditions, so I believe it will not interfere with normal muting operation as such. I am thinking of bypassing this signal such that it is driven permanently high instead of driving it from the CPU. Not so sure whether I should try that out, and hence wanted opinions from experts on this forum. I am concerned whether it will cause problems under following scenarios:
1. Currently, I notice that this mute signal is momentarily made low when switching inputs before it is turned back to high again. Will this cause loud noises or pop and click sounds while changing inputs if I tie it to high? Worse still, can it damage electronics or speakers?
2. It is made low during standby, but it will remain high even during standby after the planned fix. Will this cause any problems or damage?
3. Will it interfere with audyssey setup, when I need to do it for actual calibration? Again, can it damage electronics or speakers during setup after the fix?
Any more insights and/or suggestions are highly appreciated!
That is compelling me to try out some component level diagnosis and fixing if possible. I can take some chances in case I have to change the main board anyway. So, caught hold of a copy of service manual for this model from here:
and did some troubleshooting based on that. After looking into all schematics and symptoms of the problem, I suspected that a signal named MVOL_MUTE driven by the CPU chip to INPUT board is somehow not getting set to high in the beginning after power on (high=unmute, low=mute), and audyssey setup somehow brings it back. I traced it on boards and checked with a multi-meter, and it is indeed confirmed. The concerned signal remains low in the beginning, but it is set to high (3-4V) once I perform audyssey setup and then everything starts working fine. Note that this signal is not used for muting when I press mute button on the remote. It remains high both in muted and unmuted conditions, so I believe it will not interfere with normal muting operation as such. I am thinking of bypassing this signal such that it is driven permanently high instead of driving it from the CPU. Not so sure whether I should try that out, and hence wanted opinions from experts on this forum. I am concerned whether it will cause problems under following scenarios:
1. Currently, I notice that this mute signal is momentarily made low when switching inputs before it is turned back to high again. Will this cause loud noises or pop and click sounds while changing inputs if I tie it to high? Worse still, can it damage electronics or speakers?
2. It is made low during standby, but it will remain high even during standby after the planned fix. Will this cause any problems or damage?
3. Will it interfere with audyssey setup, when I need to do it for actual calibration? Again, can it damage electronics or speakers during setup after the fix?
Any more insights and/or suggestions are highly appreciated!
Comment