Sometime you can get excessive CPU when media sharing (WMPNetworkScv) is on.
This might be caused by a corrupt file.
Now this a hopeless case to investigated.
What you can try.
Make one directory e.g. C:\sound
In WMP point both Library and Rip folder to C:\sound
Stop media sharing
Delete the old library
Reboot (the magical MS reset)
Start WMP
Enable media sharing
Keep your fingers crossed.
I’m inclined to say that with an empty library (and hopefully) media sharing now pointing to this new library only, CPU should rapidly drop to 0.
If this is true, now you are in for the tedious part.
Drag/drop a bunch of files to C:\sound
The media sharing should kick in but not too long, repeat until you get the same problem.
Open the Resource Monitor, choose disk and watch the files pass by
Maybe this is the trick to detect a corrupt file