Parasound P/PH-100 hum

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I have this phono preamp and it's got hum issues. About 4-5 mv of 60 cycle at the output. It's worse in one channel, but present in both. If you look at the schematic at plexus PPH-100 mods (which has an error - C35 is not in series with signal ground, it goes from signal ground to chassis ground), it's not present at the input lines of the last op-amp, but is on the output lines. I've replaced all the electrolytics, but the hum persists. I'm not a hardware guy, but can solder and wield a scope. Any ideas where to look? Power transformer? Other caps?

Appreciate any help rendered...

Bob
 
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