Help with PROEL powered speaker repair

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Hi There. See attached schematic. This speaker came in with no sound problem. The only sound I hear is a ticking sound every 2 seconds from the woofer. I checked the lines labeled CSD on the schematic. These are the mute lines that go to the TDA7294 and the IRS2092. According to the TDA7294 datasheet, it needs a positive voltage over here to get it out of mute. I confirmed this by removing D17 and feeding a +5V here. This takes the TDA out of mute, and the tweeter works without any ticking sounds like the woofer. Weird thing is a can see a shift of DC level along with the ticking sound on my scope at pin 5 of IRS2092 woofer amp chip. I replaced this IC, no change.

My first question is, where does the TDA get the positive voltage from to take it out of mute? Q12 sinks to a negative -5,6V. Weird.... Maybe the IRS2092 sends a positive voltage out of its pin 5?? I don't understand... Secondly, If I can get the tweeter amp to work, surely the power supply is fine? I also replaced C51 and C56. I double checked all the voltages indicated on the schematic. The supply rails ±5,6V for the IRS2092 are there and clean.

Any suggestions .
 

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