Metropolix USB noise?

Hello all! I’ve been running a hybrid setup using an ES9 with my hardware rack, my other synths, and vcv rack. I’ve been having a ton of fun sequencing my sub37 with the metropolix via USB midi.

The problem is, that I’ve also been having a noise issue with a high pitched squeal, and tonight I isolated the metropolix as the cause :frowning: as soon as I unplug metropolix from USB all noise is gone.

I have it plugged in to a powered hub but it doesn’t seem to matter. Has anyone run into this issue and found a fix? Would love any suggestions, I would hate to give up thos awesome power!

Hey Venain,

Shoot me a message at Thanks!

Sounds like you have some interference making its way into your USB connection may be ? … maybe router is sharing the same outlet or a switched power supply near by … some generate ugly frequencies for its switching… I did have some problems myself with some thing similar.

Im no electrical guru or any thing but worth checking. I wouldn’t use USB hubs as they mess the midi signal.

Yeah I’ve found that with some things, especially certain power blocks, that using a laptop can make weird noise over usb if the laptop is charging. (Fun fact: if you have Bluetooth headphones that can run off of wired connection while charging, and charge both them and the laptop the headphones are plugged into off of the same power block, you can get some strange noises)

Hey all! Thanks for the suggestions!

I was able to fix my issue, it took two steps but my system seems to be noise free now (until I plug some other USB thing in i’m sure)

I stripped my system down to just the metroplix and audio interface, and found that even without USB plugged in I was getting significant digital noise, especially in the CV assign menu (with the pink LEDs).

I then tried swapping the power brick powering my system with other ones I had laying around with the correct specs, and found one that completely eliminated the noise. I honestly have no idea why, it was the same brand as the others I tried, the only difference was less voltage and less max amps.

I still had pretty bad noise once I plugged in USB though, which I solved with this doodad from amazon I’ve tried several things like this in the past and none have ever worked, but running metropolix through this completely eliminated all remaining noise.

I was starting to think i was just going to have to make a huge change to my case/power supply, I’m using a custom 3d printed case running 3x daisy chained row power 45’s with everything on flying busboards, but surprisingly I now have 0 noise at all - yay!

1 Like