Hello,
I have a Delfina Lite on one of the ZII slots of my A2000. After some fine-tuning installing the last version of the driver (4.15) and the appropriate library (in my case 4.16 patch 2), it works very well. I use it to play MP3. I use either delfmpeg in a shell windows or the delfinampeg.device with OS3.9 player. With these two program, the MPEG decoding is done by the Delfina's DSP, so you can play MP3 while you uses another program as the same time.Since I updated the library, there is no crash. I haven't made tests on the sound quality itself, but it is very comparable with the Soundblaster live 5.1 I have in my PC.
The other advantage of this sound card is that there is a CD audio input directly on the board, so you can adjust the CD volume with the delfina prefs program.