I'm trying to sync from W10 to Android over WiFi.
On the PC I've removed WMA from the list of formats supported by my Android, forcing any WMAs to be converted to MP3.
I'm now getting this error msg for lots of tracks:


When I get the error msg, my phone is still on the ‘Preparing download…’ screen. After about 5 of these messages I cancelled the whole sync process.
Any help?