I have some tests for you. My "stutter" problem always happens when moving from higher sample rates to lower, never from lower to higher, and never between files of the same sample rate.
First Round:
1) DAC: Audio Research DAC7. Computer output USB to V-Link/192, thence SPDIF (RCA) to DAC.
2) OS X 10.8.3
3) File types: AIFF to AIFF
4) Bit depth and sample rate: 24, 96 kHz changing to 16, 44.1 kHz
Begin playing the 96kHz/24 file. Then change to 44.1kHz/16 file. Stutter begins at 25 seconds. Restarting playback on the 44.1kHz/16 file clears up the stutter. I did three trials with the same two files and had the same results each time, with the stutter showing up clearly between 25 - 27 seconds each time.
I had precisely the same results when switching to two other files with the same characteristics (both AIFF, 96 kHz/24 to 44.1kHz/16).
Second Round:
1), 2) the same
3) AIFF to AIFF
4) Bit depth and sample rate: 24, 88.2 kHz changing to 16, 44.1 kHz
Stutter on the 44.1 kHz file began almost immediately. Restarted playback; no stutter.
Third round:
1) and 2) the same
3) FLAC to FLAC
4) Bit depth and sample rate: 24, 88.2 kHz changing to 16, 44.1 kHz
Stutter on the 44.1 kHz file began at 25 seconds. Restarted playback; no stutter.
Fourth round:
1) and 2) the same
3) AIFF to FLAC
4) Bit depth and sample rate: 24, 88.2 kHz changing to 16, 44.1 kHz
This was immediately after Round Three; the stutter began almost immediately on the 44.1 kHz file. Restarted playback; no stutter.
Fifth Round:
1) and 2) the same
3) AIFF to AIFF
4) Bit depth and sample rate: 24, 96 kHz changing to 24, 48 kHz
Stutter on the 48 kHz file at 50 seconds. On a repeat of the round, the stutter on the 48 kHz file started at 50-51 seconds. In both cases restarting playback cleared the stutter.
I hope that this helps -- this "stutter" issue is, for me, the big showstopper bug in MC.
I should mention that I get similar results on my other system:
Same OS
DAC: Bryston BDA-1; computer USB to V-Link II and hence via SPDIF (RCA) to Bryston
Cheers,
Scott