TremoJem
I use a motu 828mkll and it had the loud burst of white noise issue intermittently among other strange stuff happening. Tried so many different solutions and it just kept getting worse and less intermittent. Saw in the motu forum someone with the same problem. They sent theirs back to motu. I emailed motu and got a quick reply from a tech who sent me a RMA number. I sent it back to them and within 10 days they sent me a reconditioned replacement. Looked good as knew and all free of charge exect shipping to them. I had been using it for 3 yrs so I think it was out of warranty as well. The replacement had newer firmware and I haven't had any probs since. Just a thought if it keeps getting worse.

  I reported the incident to MOTU. They have me testing out some theories. I will keep you posted.