BE5 Compressor issue

[Tightpants]

https://soundcloud.com/tightpants/be5-comp

https://stompboxelectronics.com/wp-content/uploads/2023/01/BOSS-BE5_ServiceNotes.pdf

Hi All, I got an old Boss BE5 cheap from Ebay. It mostly works OK but the compressor wasn't working at all. I took it apart and found that someone had changed out the 1 microfarad electrolytic coupling caps for polyester ones but they clipped the leads of the old caps on the component side and tried to solder the new caps on to the tiny bits of the old legs sticking up. This was a bit of a mess and some of the solder joints had broken. Anyway I cleaned up the solder pads, removed the old bits and soldered in some new caps and it works now. The problem is that there is a low level buzzy distortion behind the compressed signal, which is more apparent on the note decay. I've attached a soundclip so you can hear what I'm talking about. First part of the clip is bypass and I switch the comp in about half way through.

I've also attached a link to the service manual, I checked the voltages in the compressor section around the DBX chip and everything seems to be in order but now I'm stuck! Any help on how to proceed would bve greatly appreciated! Thanks in advance, Pat 

[Tightpants]

Fixed it!

I've solved the problem and I'll leave this post up in case anyone else has a similar issue. I used an audio probe to check the signal at pin 1 (input) of the dbx VCA chip. There was no distortion so I guess the voltage follower section is not distorting the signal. I then checked the VCA output and the distortion is there at pin 8. The voltages around the chip seem to be OK so I guessed that the fault is with the VCA chip. I also assumed the subsequent mixing, tone and level sections were working as the controls seem to do what they are supposed to do. Anyway I have an old ME5, which uses the same chip so I removed it and put it in the BE5 and bingo problem solved! I'm currently waiting for a replacement chip for the ME5!