WT 400 enhance circuit and di problem

[ibanez7]

Hello To all,Wondering if i can get some technical assistant,the enhance circuit on my amp is not working,I've replaced all of the op amp chips (TL072) with no luck,also the di output is very low compared to how it use to work have to crank it all the way up to get an output signal,any technical assisatnce would be greatly appreciated.
Thank you
Roger

[Enzo]

Plug the guitar into the FX return jack, do you now have sound out the speaker? Did the direct out signal come back?

Plug the guitar into the front, now also plug a cord from FX send to FX return. ANy help?

If there are problems with those transistors and stuff in the compression circuit just before the enhance tone control, I fear that will be beyond your capability to fix.

[ibanez7]

Actually I'm not scared to repair it,I use to be a electronic tech, awhile ago,but if you can possibly give me a clue as to where to check,on that circuit i think I'll be able to figure it out,thanks for the advise,i'll try your suggestions and get back with my findings.

Thank you
Roger