Currently Being ModeratedOct 9, 2012 3:26 AM (in response to smellisrn)
Try switching 'off' iTunes Match.
Connect your iPhone physically to your main computer library.
Manually sync Music, start with an initial 'sync' containing no music.
This will result in Songs being loaded afresh - with such a basic manual Sync each Song should play fully.
If not, restore iPhone and configure from start as a 'new device'.
Once reliable service with Manual Sync is achieved, you can switch iTunes Match on.
Currently Being ModeratedOct 15, 2012 1:37 AM (in response to tjg1967)
The most reliable route to selecting certain Songs is to create a basic playlist to contain the Songs of interest.
IOS does not handle Smart Playlists well - so even if you use Smart Playlists to auto select, do copy the results to a standard playlist for reliable synchronisation.