- I have the very same issue with an MRX500. It is definately a 60hz hum and it varies in amplitude no matter what volume is set to. With mine, if I turn it ON/OFF repeatedly it will eventually go away. I thought it might be an intentional software virus(so you had to send it in to get it fixed) because it always seem to happen about the same day every month. Now it does it randomly and way more often.
- It is most likely a bad or cold soldered capacitor in the power supply circuit.
- Has Anthem given you an estimated repair cost?
- Have you come up with any answers?
- I'm going to check the circuits with an oscilloscope and see what I can find, I wish I had schematics it would be a lot easier. The problem is, I never know when it will start to hum.
- I'll let you know if I find anything.
