Not quite clear from your message if I'm short or long. Do they play OK? Does wvunpack say anything?
I started with "good" wavpack files that were created outside MC.
Wv to ape conversion with MC12 produced slightly short ape files. Otherwise these ape files were correct.
For checking the Monkey's Audio encoding part separately I tried wav to ape conversion. This had no problems.
Ape to wv conversion produced files that can be decoded with correct pcm data, but the reported file lenghts were incorrect in foobar. (e.g. 43.5 s instead of 29 s) "wvunpack -v" reports this:
E:\X\Wavpack\wp44>wvunpack -v *.wv
WVUNPACK Hybrid Lossless Audio Decompressor Win32 Version 4.41.0
Copyright (c) 1998 - 2007 Conifer Software. All Rights Reserved.
Get _Innocuous.wv:
file is missing 353466 samples!
Return_Of_The_Tempel.wv:
file is missing 639450 samples!
Wild_And_Blue.wv:
file is missing 639443 samples!
**** warning: errors occurred in 3 of 3 files! ****
The original source wv files are fine:
E:\X\Wavpack\wp44>wvunpack -v *.wv
WVUNPACK Hybrid Lossless Audio Decompressor Win32 Version 4.41.0
Copyright (c) 1998 - 2007 Conifer Software. All Rights Reserved.
Get _Innocuous.wv:
verified Get _Innocuous.wv in 0.24 secs (lossless, 29.33%)
Return_Of_The_Tempel.wv:
verified Return_Of_The_Tempel.wv in 0.36 secs (lossless, 32.71%)
Wild_And_Blue.wv:
verified Wild_And_Blue.wv in 0.34 secs (lossless, 37.27%)
**** 3 files successfully processed ****
I used the default Wavpack (lossless, normal, 1) and Monkey's Audio (normal) compression settings in my tests.