The same thing is happening for me. I was thinking perhaps this was an intended 'feature'. Song on front speakers fades out as new song fades in on rear speakers. Really, for folks that have good quality speakers all-around, this isn't a bad feature.
However, for those who want the main focus to be the front speakers, as I do, it is a problem. For the most part, every other song swaps between front and back. The 'surround' effect switches opposite to the main output, so that when the rear speakers are playing the main output, the front speakers are playing the surround.
I'm using ASIO Output with a WaveTerminal 192X soundcard. Replay gain is on. Output format: 32 bits. Channels: 4 channels - JRSS 2.0. Sample Rate: Source Sample Rate (I need a faster processor before upsampling). Crossfade: Aggressive: 6 seconds. Seek Smooth normal. Stop: Fadeout Normal (Stop does NOT fade out though, but that's another problem).
Basically, I don't think the swapping is a bad idea, if you can provide a way to turn it off. It'd even be cool for folks with 4 identical speakers to 'rotate' the image song by song: Song 1: LF+RF, Song 2: RF+RR, Song 3: RR+LR, Song 4: LR+LF. But you do need a way to turn it off.
I tried smooth fading, and that didn't help. I tried Gapless, and that didn't help either.
However, I did find a way to stop it! I turned off the "Do not play Silence" feature. [/u] When that option is unchecked, the problem goes away. So that'd be a good place to start looking. But the problem with leaving that turned off is that it seems to totally eliminate the crossfading that I want to use. So I have the choice of No crossfading but proper channels (leave "Do not play Silence" unchecked), or Crossfading, but channel swaps every song (Check "Do not play Silence").
I haven't updated from 11.0.105, because other than this particular problem, it works real well, and I'm not sure the newer versions will be as good or as stable. (Any hints on that one?)
Media Center Registered 11.0.105 -- C:\Program Files\J River\Media Center 11\
Microsoft Windows 2000 5.0 Service Pack 4 (Build 2195)
AMD Athlon 1178 MHz MMX / Memory: Total - 753 MB, Free - 444 MB
Internet Explorer: 6.0.2800.1106 / ComCtl32.dll: 5.81 / Shlwapi.dll: 6.00.2800.1584 (xpsp2.040720-1705) / Shell32.dll: 5.00.3900.6975 / wnaspi32.dll: 4.60 (1021) , ASPI for Win32 (95/NT) DLL, Copyright © 1989-1999 Adaptec, Inc. / Aspi32.sys: 4.60 (1021)
Ripping / Drive F: SONY DVD RW DRU-510A Mode:Normal Type:Auto Speed:Max
Drive G: LITE-ON LTR-52246S Mode:Normal Type:Auto Speed:Max
Digital playback: Yes / Use YADB: Yes / Get cover art: Yes / Calc replay gain: Yes / Copy volume: 32767
Eject after ripping: Yes / Play sound after ripping: No
Burning / Drive F: SONY DVD RW DRU-510A Addr: 1:0:0 Speed:24 MaxSpeed:24 BurnProof:Yes
Drive G: LITE-ON LTR-52246S Addr: 1:1:0 Speed:52 MaxSpeed:52 BurnProof:Yes
Test mode: No / Eject after writing: Yes / Direct decoding: Yes / Write CD-Text: Yes
Use playback settings: No / Normalization: None