PC Media Players - significant SQ differences?

I have been trying some of the media players offered on the net like Media Monkey and Songbird. What I don't understand is why does VLC sound so much better? the other 2 players make the sound veiled. Is there a PC setting or program setting that needs to be adjusted on the other players or is VLC that much better, the difference is significant. FYI I am playing FLAC files from a laptop to a MyDac.
The biggie (assuming you're using Vista, 7, or 8) is to use WASAPI for bit-perfect output. When I tried Songbird a couple years back, the WASAPI plugin kept crashing it. Today I use foobar2000 when playing directly off my PC. J.River Media Center is very well regarded (I haven't used it), and plays nice with WASAPI. As far as why VLC sounds better - I don't know - apparently it's not bit-perfect. I'd be sure to set the volume on each player to max, and adjust only on your headphone amp, powered speakers, whatever.

Whatever else it is, I'll come out and say you're not nuts. I've definitely noticed SQ differences among players, and have never completely pinned it down myself!
I am not familar with VLC but I tried the other two media players & liked J. River much better. Now I am using J. River as the gui and JPLAY for the playback. For a vinyl lover I am very surprised how good it sounds. You can try J.River for free but JPLAY needs J.River & will set you back 100 EUROS : it is well worth it. Once you purchase a license from JPLAY they send you the upgrades for free.
Depends what WASAPI you speak of. I know several people with JRiver 18 on their PC's who can't use WASAPI, but can use WASAPI event style. Computer Audiophile and Six Moons have the best write-ups I've read in English, although the forums like most forums are chock full of conflicting opinions about best media players and SQ.
This is a complex question. There are mixers,CODECs and DSP as well as floating-point math in the players. Any of these can have issues or bugs and they usually do. Offset, which is the number of leading nulls before the first bit of music starts also matters. Some players change this.

It is well-known that using itunes on a PC sounds a lot different than on a Mac for instance. Even different revisions of the same player can sound different, ala Amara and Pure Music.

I dont understand exactly why eqch player sounds different,but I have discovered over time which are the best sounding ones.

Steve N.
Emoirical Audio