Sorry to hear of your disappointment. However, the Firefly forum is not the right place – since Firefly is a server, it is not itself responsible for any change to the quality of the sound. And since you were using FLAC, there should of course have been no difference.
However, if you go to the Roku forums you will see that there has been considerable discussion relating to sound quality that some (but not all) users have experienced with the SoundBridge M1001. This is apparently due to the fact that the M1001 hardware cannot natively support the 44.1kHz sample rate of CD media (M500, M1000, M2000 don’t have this limitation). Work in investigating / resolving this with a possible improvement to the sample-rate convertor is still geing undertaken by Roku.
Suggestion for Ron… When looking at support for configurable transcoding plug-ins to Firefly, wouldn’t it be cool to be able to decode FLAC to WAV and then also hook in a Sample Rate Convertor for the M1001 users. Not that you don’t have enough to do already… 🙂