Det verkar vara en hel del strul med Leopard:
"We have been working hard on supporting OS X Leopard since its introduction to
developers at WWDC in 2006 for many months (including some period of time prior to
Leopard's release). As is often the case with entirely new major OS versions, there
were some quick "dot" releases after introduction. Many of the problems that Apple
addressed in these dot releases were critical to improve OS X Leopard operations
(you can read about some of them on the support section of Apple's website). These
improvements and fixes were very valuable to a broad base of Mac users.
Unfortunately, the currently shipping OS X Leopard release, 10.5.2, contains some
changes that actually caused problems with Pro Tools (and some other apps as well).
In our case, the problems included audio interfaces not being recognized by the
computer, track counts dropping to near zero, and errors coming up during normal
operation. Some of you who may have experimented with Pro Tools and OS X Leopard
10.5.2 may have encountered some of these problems." *
* Dave Lebolt, general manager of Digidesign