Kenwood KR-77 with a weak left channel

[Mikethenewb]

What would you recommend I do with a vintage Kenwood KR-77 with a weak left channel. Should I recap the entire unit? Is there another potential source for this problem that might not require an entire recap?

 

[ivandezande]

A ton of known bad 2SC458's in that thing and others. Replace those for starters. Could be a lot of things, including caps. Controls all clean?

 

[Mikethenewb]

The controls have been sprayed down with deoxit.

 

[elnaldo]

Controls and switches are the first thing to fix (clean). "Tape-monitor" switches, function selectors, speaker selectors, loudness switch, all them use to introduce imbalances, specially those you never use. Move them all, a lot of times, then start with the electronics.

In my amp I had a weird freq response in one channel, it was a combination of "loudness" and "high filter" switches modifying the response.