First, here's the relevant equipment: a Marantz 8802A pre/pro, a WDTV Live Hub, and an Emotiva XDA-2 Gen 2 DAC. The Emo is about a year old, and I've been quite happy with it. I usually use it as the DAC between the WDTV and the 8802. but I also have the WDTV connected to the 8802 via HDMI. But, here's what's bugging me: some of the tracks on the WDTV exhibit a raspiness in the sound when playing through the Emo. I have a mix of (mostly) FLACs and (some) mp3s on the WDTV, but the offending files I've encountered have been FLACs (all of which I ripped myself from my CD collection). If I play the same track from the WDTV via HDMI, or via HDMI through my Oppo 103 directly from my computer, no raspiness. I've switched out the Toslink cable between the WDTV and the Emo, as well as the analog RCAs between the Emo and the 8802. No joy. Any idea what the problem is? The DAC in the 8802 isjustthisclose to the Emo, and if I can't fix this I'll probably sell the Emo. But I would like to discover a fix before I give up.
The XDA-2 ONLY plays PCM digital audio. Whenever you play something like a FLAC or MP3 file, it is being decoded by your computer or media player, (which is just a special purpose computer). The resulting PCM is then sent to the XDA-2.
Because FLAC is a lossless format, anything that decodes it CORRECTLY delivers exactly the same audio as was originally encoded in the first place. MP3 ENCODERS vary considerably, but the decoders are supposed to follow a standard.... although some seem to do extra stuff in an attempt to improve the sound of bad files.
Therefore, if, with a FLAC, what comes out sounds different than the original, then there are only three possibilities: 1) whatever you're using to decode the FLACs is NOT doing it correctly (or the encode itself was bad) 2) the FLACs are being decoded correctly, but getting messed up by something downstream - like a digital volume control or sample rate conversion (they could be doing some sort of processing or conversion on the way to HDMI....) 3) the data is correct but there's something else wrong with the signal (the only possibility there is jitter - and any problems caused by jitter will disappear when you enable the XDA-2's ASRC)
It's also possible that the "raspiness" you're hearing is really there in the original, and some of your other equipment is FAILING to play it accurately (raspiness included)