What shall I do about this?
I’ve tried a few things, including rebooting, deleting inactive clip plugins. There are no plugins in my Master section.
Here’s what other stuff looks like:
Even if there is no plugin, try to use the Reset button on the Master Section.
If this is not enough, and despite the error message, the problem could come from the source, the montage. Hence try to disable some plugin to see where the problem could come from.
Thanks. I’ll try it. Wavelab 12 opened the montage fine, and rendering went fine. It seems the conversion to a new type of montage compatible with W12 seemed to help.
That said, I will try to fix my Wavelab 11 with a reset too. I always like using the same version of a program that my projects are created with.
Hi! Did you fix the problem ? I’m having the same problem 
I used Wavelab 12.
Or PG’s advice I’m guessing might have worked. Have you tried it?
Oh thanks for your answer!!!
Yes I’m using WaveLab 12 too no problem at all with version 11, I’m still waiting for some advise
I got the same error message when mastering a session at 96kHz. I was trying to export an AAC/M4a file from the montage, but it wouldn’t finish rendering and spit out the error message. In my case, the solution was to export a 320kbps mp3 file instead—which wavelab 12 did with no problem. So it seems like there’s an issue with the m4a encoder at higher sample rates (because I normally master at 48khz and I never have seen this error message before). Hope that helps.
take a look at this thread about the issue - you need to explicitly specify sample rate in the encode parameters in your encode preset:
https://forums.steinberg.net/t/320kbps-aac-encode-from-96k-failing-in-wl12-mac-os/899285