I have a KGSS-HV that I acquired years ago from a local builder. It has Sanyo parts and +/- 400V BHSE power supply. I started using it again last week after years of storage and it seems to be working great with my L700. Question: Does the KGSS-HV need periodic maintenance? I ask because in troubleshooting my SR-009 hum on the right channel, I read about DC offsets and balance. Are these something I should be checking periodically?

I built my Carbon amp 5 years ago, decided to check it as I bought new X9000’s the offset was 20 V off on one side..Components age like anything else it’s worth a check. Warm up the amp for an hour, check your power supply test points and measure your bias, balance and offset voltage should be around 0V +/-200mv for each rails