I have a Dream, Lion and Knuckles connected to the MC4 Pro via a UGREEN USB C hub into the host port.
When this hub and these pedals are connected there is a noticeable constant clicking sound in the audio.
Everything is powered via a CIOKS DC7.
My googling so far has lead me to think some kind of USB isolator might be the solution.
Just wanted to check it there might be anything else to try and if anyone has a source for a USB C isolator?
Have you tried using a different power source for the MC4 Pro?
I haven’t - I have thought that would introduce more potential issues! I can give it a go though.
I’m assuming the MC4 Pro is on its own jack on the Cioks DC7? Make sure you’re doing that first. If it persists, one of the easier things to try is to power the MC4 from a USB power bank, which won’t create a ground loop because it’s not connected to anything.
As far as USB isolators are concerned, I usually advise people to use one of the cheaper ones based on the ADUM3160 chip before going fancier. There are a handful with USB-C on one end that could be used directly with the MC4 Pro ; otherwise, you’ll need some USB adapters since most are USB Type A connections. These isolators don’t really allow for high data speed, but that shouldn’t be a problem for MIDI.
If you can buy from somewhere with an easy return policy so you can try it out, you might consider trying a device like the Topping HS02, which I use when I get USB ground loops. It’s a bit more expensive, but I’ve found it useful. You connect one port to the host, the other to the device (or in this case, the hub), and if needed, you connect a separate USB power source (the DC7’s USB port is useful here).
Yes the MC4 Pro has it’s own power, I will try it on a powerbank source.
I don’t know why I didn’t think of adaptors for the USB isolators, I think just because I usually hate the idea of introducing more parts, I’ve ordered a cheap ADUM3160 based one and some adaptors to at least test it.
I’ll have a look at the Topping HS02! Thanks for taking the time to reply!
Yeah, one reason i like the Topping HS02 is that it’s just a box with ports for plugging in normal USB cables. Otherwise you have to get all these male to female adapters and it gets annoying.
Yay! Note that the ADUM3160s are a little notorious for burning out fast, so you may either want to have an extra on hand or upgrade to a fancier isolator later on.
