Hi Kenalker. I used an oscilloscope to trace the circuit. I started at the Cirrus Logic chip (link: CS4265). This is the DAC chip that converts digital signal to analog. That analog signal is then amplified. I monitored the analog outputs from this chip and could 'see' the audio signal being output properly from this chip. I then traced it to those two capacitors. I don't know the exact role they play (maybe they shunt high frequency signals to ground). In any event, they are between the DAC chip and the NE5532 OpAmp chips. I wasn't able to detect any signal on the input of the OpAmp chips, and found that replacing both of these solved the problem. As I mentioned here in my earlier post, this fix has worked many times for me.
The first thing to confirm is whether or not the digital signal is working (which you have done). If the digital output is working, then I'd strongly suspect that these caps are the problem. If it isn't working (as in one of your units) then you've got some other kind of problem. I would try to swap the main circuit boards in your two devices to confirm that the bad device has a bad audio board. I once saw a device where the main board stopped sending a digital signal to the audio board. By using your 'known good digital' audio board you can confirm that the main board is generating a good digital signal.
The second thing... I would replace the power supply caps if you haven't already. Based on age alone they are likely to fail soon, and these are cheap parts to replace. The power supplies operate using high frequency SMPS power supplies, not just AC that's been through a transformer and rectified/smoothed. Poor caps could be letting through high frequency transient voltage spikes that you might miss by looking at voltage levels.
In my experience, over 90% of the bad/low/no audio problems are these two caps, but I have also found a few devices that I wasn't able to repair. The best solution I found when I couldn't repair was to use otherwise dead devices. Sonos created a lot of those back when they bricked devices that people upgraded to S2 (before they changed their bricking policy). There were a lot of those devices offered for parts on ebay a couple of years ago, but they are much less frequently offered now.
The first thing to confirm is whether or not the digital signal is working (which you have done). If the digital output is working, then I'd strongly suspect that these caps are the problem. If it isn't working (as in one of your units) then you've got some other kind of problem. I would try to swap the main circuit boards in your two devices to confirm that the bad device has a bad audio board. I once saw a device where the main board stopped sending a digital signal to the audio board. By using your 'known good digital' audio board you can confirm that the main board is generating a good digital signal.
The second thing... I would replace the power supply caps if you haven't already. Based on age alone they are likely to fail soon, and these are cheap parts to replace. The power supplies operate using high frequency SMPS power supplies, not just AC that's been through a transformer and rectified/smoothed. Poor caps could be letting through high frequency transient voltage spikes that you might miss by looking at voltage levels.
In my experience, over 90% of the bad/low/no audio problems are these two caps, but I have also found a few devices that I wasn't able to repair. The best solution I found when I couldn't repair was to use otherwise dead devices. Sonos created a lot of those back when they bricked devices that people upgraded to S2 (before they changed their bricking policy). There were a lot of those devices offered for parts on ebay a couple of years ago, but they are much less frequently offered now.
Hi Zimmi10. Are your replacement caps the same capacitance rating (they look large)? If they are correct, then double check the soldering. These pads are extremely tiny and hard to solder well. Check for good connections, but also check that there aren't any accidental bridges to nearby components/traces.
It may be helpful to use TP1018 and TP1022... These are test points for the two negative legs of the two capacitors... You can solder the negative legs to these points instead of the original points...this works well when the replacement caps are larger than the original ones.
HI timc995. Thanks for all the advice! You've done some reverse engineering already. I don't suppose you've drawn any of that up in schematic form? I can get the CS4265 data sheet and go from there, but I don't want to re-create the wheel. Also, have you found any other caps that go bad regularly besides the two mentioned and the power supply caps? I'm going to place an order and want to ensure I don't end up needing one SMT cap after replacing ten.
BTW, when I said I had no digital output, I just hooked the toslink output into my stereo to see if anything was coming out the toslink cable; I didn't look at the output of the DAC itself with my scope. How are you hooking to the DAC? Have you made a jig that allows you to have the digital and analog boards side-by-side (rather than stacked) so the digital board is not covering up the analog board, or are you removing the digital board, soldering wires onto the analog board, and then re-attaching the digital for each test?
Sorry but I didn't create any schematics. The 5 power supply capacitors and these 2 on the audio board are the only ones I've replaced. I'm sure that as these (repaired) devices age, other capacitors will start failing and causing problems but I haven't seen that yet.
Using the toslink output to see if the device is outputting the signal is what I meant in terms of determining if the board is propertly processing digital.
When I was debugging the signals on the audio board, I ended up temporarily soldering fine gague wires to the board and feeding the wires out from under the main board to the oscilloscope. I contemplated creating a ribbon cable to temporarily connect the main and audio boards so that I'd have access to the audio board without having to solder temporary wires, but it turned out that I found the problem I was looking for fairly quickly so didn't end up creating the ribbon cable.
Using the toslink output to see if the device is outputting the signal is what I meant in terms of determining if the board is propertly processing digital.
When I was debugging the signals on the audio board, I ended up temporarily soldering fine gague wires to the board and feeding the wires out from under the main board to the oscilloscope. I contemplated creating a ribbon cable to temporarily connect the main and audio boards so that I'd have access to the audio board without having to solder temporary wires, but it turned out that I found the problem I was looking for fairly quickly so didn't end up creating the ribbon cable.
NEWBIE here ... looking for REPAIR help on TWO defunct Sonos ZP-90s (one was in current use until 12 hours ago, one is "dead" spare)
Upon restart of Sonos S1 system (5-6 Zp-90s, ZoneBridges, and 4-5 sets of Sonos speakers), our favorite ZP-90 "YARD" started flashing RED on front
THREE quick RED flashes followed by FIVE quick RED flashes ... repeat infinitum ... newbie Sonos tech support was either unable/unwilling to look up this particular RED light sequence as error code
Have tried FACTORY RESET to NO AVAIL ... nice Sonos tech support lady (in Philippines) simply did the usual rote response after 30 minutes of her reading their diagnostics DB ... "we can give you 30% discount on NEW Sonos gear ... your unit NO longer supported" ... which of course we already knew, having been down that road several times the past 10-20 years of living with Sonos gear
ANY CLUES on what to try next? Any DIYers willing to repair such gear for 70 year old retired rock musician in SF Bay area? I have other spare ZoenBridges I can share with the community (which I bought from another musician friend's estate when he passed)
THANKS (!!!)
--Aaron in San Mateo, CA
Upon restart of Sonos S1 system (5-6 Zp-90s, ZoneBridges, and 4-5 sets of Sonos speakers), our favorite ZP-90 "YARD" started flashing RED on front
THREE quick RED flashes followed by FIVE quick RED flashes ... repeat infinitum ... newbie Sonos tech support was either unable/unwilling to look up this particular RED light sequence as error code
Have tried FACTORY RESET to NO AVAIL ... nice Sonos tech support lady (in Philippines) simply did the usual rote response after 30 minutes of her reading their diagnostics DB ... "we can give you 30% discount on NEW Sonos gear ... your unit NO longer supported" ... which of course we already knew, having been down that road several times the past 10-20 years of living with Sonos gear
ANY CLUES on what to try next? Any DIYers willing to repair such gear for 70 year old retired rock musician in SF Bay area? I have other spare ZoenBridges I can share with the community (which I bought from another musician friend's estate when he passed)
THANKS (!!!)
--Aaron in San Mateo, CA
Looking for REPAIR help on defunct Sonos ZP-90
Reboots as NEW DEVICE fine and is found by SONOS app and added fine ... White light normal on front ... yet NO AUDIO out ... have swapped IN other similar ZP-90s and they work fine ... so the AUDIO out is NOT working on this unit .. S/N 1009-00-DE-58-29-99-5A-F
ANY CLUES on what to try next? We are willing to repair to repair this gear
(I have other spare ZoneBridges I can share for parts which I bought from another musician friend's estate when he passed)
THANKS (!!!)
Aaron in San Mateo, CA
Retired rock musician in his 70's
Reboots as NEW DEVICE fine and is found by SONOS app and added fine ... White light normal on front ... yet NO AUDIO out ... have swapped IN other similar ZP-90s and they work fine ... so the AUDIO out is NOT working on this unit .. S/N 1009-00-DE-58-29-99-5A-F
ANY CLUES on what to try next? We are willing to repair to repair this gear
(I have other spare ZoneBridges I can share for parts which I bought from another musician friend's estate when he passed)
THANKS (!!!)
Aaron in San Mateo, CA
Retired rock musician in his 70's
You should also replace the power supply capacitors. There are 5 electrolytic caps in the Zp80/Zp90 models and they all degrade with time. Try those first.
If that does not work, then replace the two capacitors circled here, and you should be back in business. I have done this on multiple devices successfully. Note that this will work only if you have very low output volume on the analog outputs but your digital works. If you have NO volume out at all on analog, then this fix will not work.
Attachments
Last edited:
This sounds like a bad flash chip, and in that case you are out of luck.
On your other post about no sound, see my post just above this.
I have the older version of the Sonos ZP90 with a serial number starting 0902 00, the SMPS was dead which I have replied and have a constant 13.28v and 3.235v on the four pins on the top PCB. I believe this to be a Gen 1, however, when connected to the line out of my NAD 3130 and the line in on the ZP90, I have an extremely low volume, I have to turn the volume to Maximum on my Play 5 Gen 1 to hear anything. Have read most of the posts re this issue, I have replaced 22uf, 47uf and 2.2uf caps as recommended in this post but this has still not restored the volume. The PCB is not marked with the component ID numbers, what else could be pulling the volume down and comments or suggest would be welcomed.
REgards
David.
REgards
David.
Replace the cap that is circled in the image attached to post #6 in this thread.
If that doesn't work, then you have a bad connection on one of the replaced capacitors.
If that doesn't work, then you have a bad connection on one of the replaced capacitors.
Thanks for the reply, I had replaced the cap marked in post 6 with a 10uf 50v, I re soldered all the caps I replace and still have no volume. What else could be causing this problem?
Just a quick "thank you" to everyone that has contributed to this thread. I've recently been repairing several of my defective ZP80's (replacing the 4 filter capacitors on the power supply). One of them had very low output on the right channel, and this thread pointed me in the right direction to replace the decoupling capacitors between the DAC and the OPAMP. I didn't have any SMD electrolytics on hand, so I used 2.2 Wima film capacitors, which did the trick.
Good to note about the 22uf on the analog supply.
Thanks again!
Good to note about the 22uf on the analog supply.
Thanks again!