I’ve just installed Wavelab 8 (32-bit) and Quicktime 7.7.4 on my Windows 8 laptop.
Converting is running superb with all 8 cores - only at the beginning …
I noticed that Wavelab 8 permanently swaps between the windows “Operation in progress …” and “Batch Conversation” and bring the one or the other always on top. Seems to be a bug in Wavelab 8 (maybe only with m4a files - didn’t had this problem with 10000 .wav to .mp3).
When starting with "Operation in progress … " window - not with the first files(!) - then all 8 cores are not used anymore - only one file after the other. Seems to be another bug.
Also I miss the output of the converted file to the source folder. But with the tags stored in the file I’m able to re-create the original directory structure with Tag & Rename, etc.
A follow-up problem of only one output folder is that duplicate file names (unique in each sub directory) have to be renamed before this batch starts.
However - after ~ 50 minutes 650 files have been converted and is still running without any problems.