Thank you for the welcome. The hum is really faint (need to put my ear within a foot to notice) if that means anything. My D-75 works but I would like to be proactive so I'm wondering, does anyone have experience with rebuilding / restoring D-75 or know sites documenting it? I found this but it's somewhat vague. Thanks in advance.
I recently acquired a used D-75 and it works. It's an older version with round knobs however, I notice a faint hum from the amp itself (not from the speaker). Is it normal for older D-75? If not, what are the possible culprits and remedy? Thanks in advance.