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IIci: no internal sound but sound on external speaker

NE555

6502
All caps replaced, traces seem ok, replaced the speaker jack, but the issue is still there. Any thoughts? There is either no sound or sound with the external speaker plugged in.

 
Are you sure the internal speaker itself is good? Also, I wouldn't be surprised if there's some trace damage around the audio circuit given that there are some electrolytics near the sound chips and the speaker jack. After looking at the schematic, I'd recommend checking for continuity between C2 and R10, and between R10 and J23 (internal speaker connector).

 
Isn’t there a switch in the headphone connector?

Not sure if all Macs had it but some did at least.

If it gets stuck it disables the internal speaker.

 
Isn’t there a switch in the headphone connector?

Not sure if all Macs had it but some did at least.

If it gets stuck it disables the internal speaker.
Yep! I once went through the trouble of changing the sound IC on an LC II only to find that the sound still didn't work. Plugged headphones in and sound was load and clear; unplugged them and sound was working fine again. From now on that will be the first thing I try before I go changing ICs.

 
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