QSC TouchMix 16 sound problem fixed (other touchmix versions may also get this)

Hi, I have a TM16 that is SN: LLE0G1192, which I believe indicates it was manufactured in Dec 2014. I bought it used about a year ago and soon discovered Aux 3 had little to no output, so I simply didn't use that output when gigging. I finally decided to tackle the Aux 3 issue and discovered this thread. I'm glad I did!! The info here has been invaluable to me. I opened my TM16 up and found not only a bad cap (bulging) on Aux 3's output, but bulging caps on both the left and right Mains (all 4 caps). The Mains have been working ok as far as I know but I'm pretty sure it was just a matter of time before I would have had a failure and most likely at a gig! Anyway, I have new caps on order, and I've removed all the output caps for the Mains and Auxes 1 thru 6, while I wait for the new caps to come in. I have pics to post of the bad caps and PCB where they were removed from, plus pics of the display ribbon cables and Master Controller connector J1401. Disconnecting J1401 was not easy as it's been connected for 9+ years. I'm thinking that the plastic on the connector and surface mounted socket it goes into have been baked by the above average heat that the TM16 generates and they more or less fused together. I worked them apart little by little using two jeweler's screwdrivers (one on each side of the connector) and luckily nothing broke. Pulling on the wires like I saw in a You Tube video was not an option to me because the wires would not take the strain of the pulling given how tightly fused together the connector and socket had become. Anyway, that's it for now. Once I get the new caps installed, the unit put back together, fired up and checked out, I will return to post the outcome of my repair endeavor.
 

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Hey Paul,

The backwards capacitor problem affects both the TM8 and TM16 with the following main circuit board part numbers:

PC-610203-00 (TouchMix-8) or PC-610303-00 (TouchMix-16)

So if you have a main circuit board with these part numbers, you need to remove and either replace or reinstall the old capacitors but in the opposite direction of what is shown on the circuit board.

Hope that helps.

Cheers,
Brian
Hello Brian, apparently like many others I have low output problems, probably caused by the caps of the QSC Touchmix 16. In your message you indicate that mainboards with the number PC 610303-00 should have the poles reversed. My mainboard shows PC 610303 REV C. Would this board be OK, so replace the caps as they are now on the board?
Thank you in advance for your answer and kind regards
Hans Hulsenboom
 

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Last edited:
H, all I just found my old post von exactly one year ago.At the I got a qualified contact via the German headquarter of course see here and I sent a mixer to the European self-center in the Netherlands. Costs me around 150 Euros to fix the problem incl.delivery.
More less one year after the last problem I have the next mega issue with the TM 16. After a sudden power loss the touch display did not react anymore.
God bless that I have control with a tablet to the mixer. What a poor design. To send the mixer in Standby you can press the hardware Button but you have to confirm with the Touch Display. This makes absolutely no sense.
All this is happened before a gig. In 2 days I have the next next gig and I need a mixer. I have enough now. I think I will again fix the mixer via a service center and then try to sell it.
I'm playing music over 30 years now. I clearly have to say that this is the worst piece of gear I've ever had. It would be perfect if it would constantly work. But you can not trust this peace of gear. I'm totally disappointed.
 
H, all I just found my old post von exactly one year ago.At the I got a qualified contact via the German headquarter of course see here and I sent a mixer to the European self-center in the Netherlands. Costs me around 150 Euros to fix the problem incl.delivery.
More less one year after the last problem I have the next mega issue with the TM 16. After a sudden power loss the touch display did not react anymore.
God bless that I have control with a tablet to the mixer. What a poor design. To send the mixer in Standby you can press the hardware Button but you have to confirm with the Touch Display. This makes absolutely no sense.
All this is happened before a gig. In 2 days I have the next next gig and I need a mixer. I have enough now. I think I will again fix the mixer via a service center and then try to sell it.
I'm playing music over 30 years now. I clearly have to say that this is the worst piece of gear I've ever had. It would be perfect if it would constantly work. But you can not trust this peace of gear. I'm totally disappointed.
Pop the back off and see if the ribbon cable came unplugged. We had that happen on a few touchmix 8 units and it was a really easy fix.