Hissing and popping sounds from Korg O5R/W
Hi Phil ,( 4 April 2017 )
I have the same problem with the noise , but from both audio channels .
The hissing sounds , happens after about 5 minutes , when the module
is warmed up , which tends to make me think it is power related .
In addition , the total volume begins a degradation .
(BTW , the power adapter checks out )

I opened the module up , and noticed that there are very few sizeable capacitors,
so I am de-soldering them , and planning on replacing these few as a start . The cost of the capacitor(s) is cheap .
The overall interior is clean , with no electrolyte leaks .
I'll let you know the results , as I really value this unit , that I purchased , when Korg first introduced it 1994 . I guess I'm lucky that it lasted this long , in my home studio .
I recently purchased a used Korg X5DR , and anticipate using the two modules together in my arsenal of 8 various sound modules .
Mike W.

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