Attempts to fix 3.5mm audio socket on Sony D-33 Discman

I bought this D-33 with a known issue of no audio out the right channel via headphone jack (line out however is fine), having opened it up I noticed a hairline crack on the top layer of the PCB, under what seems to be the ground pin of the headphone socket, I added a small bodge wire where I had tested there was continuity issue (only when a jack was inserted). This did not resolve the right channel being missing?

Then I noted when you start to pull the plug out, you suddenly get audio in both L & R, but I'm assuming this is just a single channel being pushed to both L & R headphones.



I mapped out where everything connects below, does it seem correct that L channel is connected to 2 pins?

I have not been able to get to the other side yet, as multiple wires need desoldering to access it easily.

Is this most likely symptoms of a broken connection I've not yet found, or broken socket? should I just wire in a new headphone socket to what I assume is the L & R channels + ground on the back of the existing socket, to rule out broken socket maybe?

 

Clean inside of 3.5mm socket with alcohol on a cotton swap (Q-tip) that has been stripped down to fit. Remove the heavy oxidation that is bound to be there. Then I would just fully re-flow the solder pads. And see what that does first.

 

Initially tried reflowing and that didn't bring the right channel back.

Finally resolved this when I found a crack just under the the right solder connection for the 3.5mm jack, traced back to the source pins on Bass Boost amp IC304 to check both left and right were working, found the via right next the pad which was also outputting signal. So just scraped some solder mask, and tacked on a little bodge wire, and she's back to stereo.



https://archive.org/details/manual_D33_SONY

 

Urgh now the damn thing is skipping and just plain crashing out of songs half way through with garbled noise, I'm assuming given these were from 1991 ish, the 34 year old capacitors can't be doing so well! and may have something to do with odd behaviour.

Counting the electrolytic caps I can see 44 of them! I haven't pulled up the pcb to see underneath but I'm assuming only a few will be the radial one's? presumably the higher capacitance/ higher voltage?

Which one's are best to focus on?

https://archive.org/details/manual_D33_SONY