Older thread but adding info due to one of the last posts suggesting BBWX4 poor sound quality. My recent install was a BBWX4 with a Fusion BB-100 black box using West Marine 4" compact box speakers. Agreed sound quality from Sirius was terrible, very staticky sounding, initially suspected the speakers but after connecting other sources to the BB-100 I got clear audio. I next suspected the RCA connections as inadequate. However, I was able to play around with the volume controls on both the BBWX4 and Fusion system simultaneously to ultimately get good audio. The magic combo was finding the right volume on the BBWX4 where I got clear audio, which I believe was on the low end of the BBWX4 output, and leaving it there. Then, the Fusion is used as the primary volume control. This got clear audio out of the BBWX4 at both higher and lower actual speaker volume outputs. I am assuming the Fusion has better audio processing capabilities than the BBWX4 which would make the above settings combination make sense at least to me. Your audio system may require a different combination of volume settings. FWIW, the BB-100 is connected to the network of both a TZT9F and TZT12F via NMEA 2k connection, not ethernet.