Meridian Unplugged - Powered by MrTechGuy.co.uk Forums Discussion Meridian - Systems 3200 loud constant buzz

In my case it was the complete failure of the 3 reservoir caps on the negative side of the supply, so the hum was 100Hz at 50% power output - LOUD! Completely recapped the speaker and all is well, but there's evidently an issue with the caps in this position - every other electrolytic capacitor in the unit measured exactly on spec and there's no sign of any earlier replacement activity. There's something either related to electrical or thermal stress about the caps on this side of the supply that's making them age faster than all the others. Trying out some Vishay alternatives with better life specs...

For my 8K’s I eliminated the hum/noise with an isolation transformer.
For my 3200’s, each speaker is plugged into a Furman wall socket plug, that
also has worked quite well to reduce hum/noise. Repair Shop did a great job
fixing my 3200’s, they have been operating without issue since repair.