I suspect it's a Steinberg problem, but since I upgraded to Cubase 5.0 or 5.5, Mastercomp or Xenon cause weird eq, phase and/or balance issues if left on the master bus when loading the song. If I delete vst and reload it, it always works fine. I think Izotope Ozone sometimes acts odd on the master buss too though. Didn't have this issue in Cubase SX. Since these plugs dont work reliably in Cubase 5 nor Wavelab (essentials at least), what host do people use for mastering?

Hello,

Which exactly version of PSP MasterComp and Xenon do you refer to and please write more about your system version and configuration.
Please try latest versions of our plug-ins.

Regards,