Cubase stops playback when changing output bus - at random

About to give up on this one,…
This is a reoccurring problem, but happens randomly.

  1. I have a live project for mixing, using x2 aes16e pcie cards and two lynx auroras to an analogue desk
  2. Randomly when I add an output bus, cubase freezes for longer than normal time, then wont play audio again on that project only. Everything else works on the machine. including other non affected cubase projects.
  3. I can fix it sometimes by messing around with the drivers, selecting and de selecting asio, changing buffer, but not all can be fixed. I have to export each track (which works) then start again in a new project. rendering my use of cubase for my commercial studio… useless…

Totally random, but now have 5 projects where this has happened.
Lynx audio spent a LOT of time on my machine with teamviewer and cant solve it, or believe its a lynx issue, for whatever reason cubase wont talk the the lynx drivers after the problem happens, but its project specific.

can anyone help?

PC, 32 GIG, 64 BIT, ASUS Z97-A Motherboard

i use artist 8.3

Do you stop playback before adding a new bus ?

yep, stop playback before adding…