Technics SU-8080 high buzz or hum

Hello, I have resently perchased a Technics SU-8080...
The sound is great, but useing the direct mode I have a high buzz or hum...
Via tone is quiet... 🙂
Does this mean something for a technically advanced gear guy?
I have cleaned the switch already...
All the best...
Chris
 
thankyou for your reply!
well, the difference between direct and via tone is not soooo big...hahaha...
it still sounds great even through via tone... for me... hahaha
before replacing some resistors and caps, i will leave it to please just as it is!
all the best!