Good news that you have it basically working
Can you post some additional information about the radio streams that you can play, and about the (flac?) files that you cannot play? The difference between the source that DOES play, and the source that does NOT play will probably help identify the problem.
For example, a radio stream I often listen to is displayed with this information in the Rune UI:
Stereo, 24 bit, 44.1 kHz, 128 kbps
A typical hd flac file I have is displayed with this info:
Stereo, 24 bit, 192 kHz, 3175 kbps
(both sources are 24 bit, but note the differences in clock rate and data rate

)