EMU Proteus/1 No Audio in Left Channel, Sub 1 or Sub 2

Wonder what happed to my EMU Proteus/1?
It was given to me by my cousin in 2018 and used it extensively throughout 2019 until the start of the Pandemic when I put it in storage(no cruise line travel). A week ago I took my equipment out of storage then tested the Proteus /1 patches with a Master Keyboard.

All was fine for 15 minutes then I hear a boom sound from my monitor speakers then a crunchy/crackly/feedback noise came out as I was playing the keys. I stopped playing then noted that the MIDI LED was flickering along with the noise/feedback. Turned the unit off then waited 5 minutes before turning it on. The noise was gone, the MIDI LED wasn’t flickering so I played a few notes.I only hear sound on my right channel but it seems attenuated and there was nothing to be heard on the left channel. Plugged in headphones and only heard notes from the Right Channel. Tested the audio outputs from Sub 1 and Sub 2 nothing came out.

Can this no audio problem be fixed at all? I understand that the Proteus/1 is essentially a box with a PCboard and a power supply unit inside. Very few components are replaceable as they are on a single board. Any advice will be appreciated. Thanks.

try to find a diagram that gives the layout of this keyboard that loud sound could be our old friend the capacitor to blame. how old is this keyboard 25-30 years old like 1989 to answer the other part of your question what happened to emu systems short story they are the guys who acquired ensoniq and ran a American company to the ground. I really miss Ensoniq when these keyboards was made in good old USA in Pennsylvania …mmm i digress. the only thing emu is making these days is over price headphones so buying parts is going to be a challenge and is going to require your inner MacGyver skills. there is mouser for capacitors if that’s what is needed remember if it was working fine and you had it in a dry place get your multitester to see the readings for the voltage. take your time you can do this.

Thanks for the advice. Too bad finding the schematic for this module would be difficult as it’s not on the web . Anyone here has a lead as where to find one