Multitamberal+Daw+VSTs Questions - Feedback Loop

[fungames]

How do you use a 16-channel QS8.1 multitamberal synth with pro tools with VSTs for arrangement? I wish to use my QS8.1 for sound generation, but VSTs only for drums. I would turn off local switch when using VSTs. The problem I have is that when I take the outs of my QS8.1(1/4") to the ins of my MX 602a(1/4"), and the outs of my computer(3.5mm) into the ins of my MX 602a(1/4"), and then the main outs(1/4") of the MX 602a into my speakers, I get a buzzing sound when my FA-06 is plugged into the via USB midi hub or USB of my computer. It also happens with the Fantom FA-06, and every board or computer. I've tried: iMac 1999 QS8.1, Mac Book Pro 16" 2021 M1 - QS8.1+FA06, MacBook Retina 15" late 2013 FA06, 2x Custom Built FA06+QS8.1.

It has been so gosh dang frustrating, and now every time Windows 10 updates or Mac does, I get driver issues where program changes won't send to the boards (QS8.1 and FA-06).

I love legacy gear and hate our new systems, but I hate using legacy gear as standalones. I prefer DAW for sequencing and not the Triton sequencer. I've done a lot of debugging, and I still have not been able to figure it out. Been debugging for nearly 20 years. Please help; I'm desperate.

I've read hundreds of pages and advice on the subject through forums and stuff, and everyone has their own solutions, all different; none have ever worked for me! Please help. What the heck is going on? I've also tried UMC404HD, M-audio, and a VSL22 interface. It creates the same feedback/USB noise as the formerly described setup.

The house is grounded, and I have a 1000-watt UPS, as well as a laptop for battery power; it is not house grounding. Unless it does not happen until a loop is created between USB devices. I've tried self-powered hubs, balanced cables, unbalanced cables, ferrite cables, iFi defender, and more; it does not help. Will someone please tell me how to spend the least amount of money and not have this happen? I only like playing the playback through the board/speakers in realtime during playback for mix down. This is why I am introducing the mixer board.

I would prefer to not spend more than $100-$200 for a long term working solution, I've already blown thousands on cables, UPS, digital audio interaces, USB hubs, etc, etc, etc, and other crappy fixes that never work!!!

Please help and thanks again,
A

[lfm]

I would try connecting FA-06 audio outs to MX602, and disconnect usb.
- any noise?

Then try DIN Midi cables from FA-06 to a midi interface on computer
- any noise?

Just drop as much usb as you can, it's a can of worms to handle.

DIN Midi isolate electrically and usb midi does not.

You mention more stuff like Triton etc, so try remove usb one by one and see where culprit is.

If not enough inputs on MX602, get a patch bay and just connect what is needed any instant.