a little help - no SID sound even though interconnect test OK?

[program_insect]

Hi, I'm nearly done with my control surface A midibox sid, but I've hit a road block.  There is no sound output from the SID module.

The core seems to be functioning fine, LCD is working, interconnect test passed, I have 12V at SID pin 28 and all the other pins look OK.  I loaded the sid test tone application, loaded fine.  However, I get no sound at all from the audio out.

Wiring looks ok, I think.  I have the 0 pin on J3 going to tip and the ground going to the sleeve.  I am using 3-conductor jacks, and I left the ring conductor open since it will be shorted to sleeve with a TS connector, right?  Suppose I had erroneously switched the two pins, would I get any sound that way?

Could this be some wiring problem to my audio jack?  If the interconnect test passed, can I fully rule out the possibility of a flaw on the module?  Could it be a dead SID chip?  Any tips at all?

Thanks ---- G

[program_insect]

Ok, I'm getting the test tone after trying a different SID.  Guess my chip was blown.  It was minty fresh out of an ancient, dusty, gummed up C64, but the chip itself was clean....