Question Trying to bring a BSR EQ 14/14XR back to life.

[Batnut#63]

First, to let everyone know I am not a professional but an amateur that has some electrical experience form high school electronics back in the day so Luckly I have been able to fix most things I have tackled with the proper guidance from someone knowledgeable. My situation is I am trying to repair a BSR eq 14/14xr to add to my 80's 90"s stereo system I am putting together. I purchased this unit and when you powered it on only one light would shine on the source side (line button), the spectrum display was completely black. After doing some research I found a video of a tech saying this was a common problem with these units. In the video he shows 2 burnt crystals (MP040, MP060) and he replaced them as well as suggesting replacing the Memory Crystal (RSCX11045R5F13013U0) position (C218). I found my 2 crystals had brown corrosion on them. I replaced both crystals and put a new memory capacitor in it. Got everything connected and turned the power on. The Source buttons started working and the Display screen lit up and showed life. Turned the power off and put cabinet back together. Turned power on again and everything was fine for about 30 seconds and the source side went black, no light on source switch, even trying source switch and dubbing switches. As I didn't see any damage to the Original Memory Capacitor I reinstalled it and the display came back on still but no change in the source side of the unit. Any help with this would be greatly appreciated as I want to add it to my Yamaha stereo system and try to recapture my joy of music I had with my stereo system I had back in my 20" in the military. Thanks everyone.