Hello,
I use Live 6.0.10 on Windows XP and I found that, sometimes, when clicking and trying to move the 'Buffer size' field in Preferences->Audio Live crashes and quits.
Note that, since I'm using an ASIO driver, the field appears to be unchangeable. Anyway I instinctively tried to change the buffer size from there and that's how I found this bug.
I usually set the buffer size from my audio interface own control panel.