corrupted sound with certain video formats

I am using Serviio on Windows 7 64-bit, with a Roku 4400 on our home stereo.
I have loaded the "Roku 4K Media Player" profile.
Now (with the Roku 4K profile loaded in Serviio) we see all our video files in Roku Media Player, with correct filenames.
However, I'm having problems with sound in some video formats. Here's what we see so far:
mp4: plays fine, audio and video
mpg, wmv: video is fine, but sound is corrupted; hard to describe exactly what's wrong, but it sounds like 3 out of every 4 samples are mis-translated or something, it's really un-listenable !!
flv: sound is good, but no video at all (I realize that's a very old format, but I have a bunch of older videos in that)
mov: either doesn't play at all, or we get sound corruption, like the mpg and wmv
My major concern is with the corrupted sound on mpg and wmv; is there some way to resolve this?
BTW, to address some points from the FAQ:
- we have a wired connection between the Roku box and our gigabit router
- the Serviio computer is a mid-range gaming machine, with an Intel Core-i7-3820 (Sandybridge-E) processor, OC to 4GHz,
and 16GB RAM, of which about half is available.
I have loaded the "Roku 4K Media Player" profile.
Now (with the Roku 4K profile loaded in Serviio) we see all our video files in Roku Media Player, with correct filenames.
However, I'm having problems with sound in some video formats. Here's what we see so far:
mp4: plays fine, audio and video
mpg, wmv: video is fine, but sound is corrupted; hard to describe exactly what's wrong, but it sounds like 3 out of every 4 samples are mis-translated or something, it's really un-listenable !!
flv: sound is good, but no video at all (I realize that's a very old format, but I have a bunch of older videos in that)
mov: either doesn't play at all, or we get sound corruption, like the mpg and wmv
My major concern is with the corrupted sound on mpg and wmv; is there some way to resolve this?
BTW, to address some points from the FAQ:
- we have a wired connection between the Roku box and our gigabit router
- the Serviio computer is a mid-range gaming machine, with an Intel Core-i7-3820 (Sandybridge-E) processor, OC to 4GHz,
and 16GB RAM, of which about half is available.