This is my EAR834p clone build. I followed Skunkies build guide on Youtube which was great! I did however implement the Thorsten and Roberts mods from the LencoHeaven forum and followed their grounding scheme. I also have a MM/MC switch on the back where the MC goes trough a pair of Lundahl LL1931 step ups transformers.
This build do however have quite a loud hum that I have not been able to get rid of.



I am no expert on ground loops but I will be building the same boards up in the very near future. Have you tried flipping the main board around and really shortening up the signal wire so there are much closer to the rca’s? The LONG grounding (LOOP!) wire coming off that main board looks like it it’s tying into power supply board but could easily just be tied directly across to main star? Easy enough to try quick!