I can't believe no one else experienced this problem? But here is your solution...
Ok this was a ll related to us upgrading Flip for Mac to version 3.1, in FCP 7.0.3 Our IT dept upgraded our OS to 10.7.5 which made our earlier version of Flip For Mac ver 2.4 go into the demo mode, forcing us to upgrade. After the upgrade the audio playback out of the FireWire connections sounded like the audio was playing in slow motion. Desktop preview worked fine. Sequence was set to DV NTSC, footage was Prores 422.
Problem showed up right after upgrade, tried new cables, tried alternative FireWire decks, nothing helped. The IT guy found the solution. Uninstalled the plugin, went to Go in the menu while holding down the option key and select "Preferences" which open user prefs. Scroll down to the Final Cut Pro FOLDER and trash the three prefs in there.
Fixes the problem. We confirmed by reinstalling the plugin, got the same problem with the audio, trashed the prefs again and whala fixed the issue.
BTW I got no help from Telestream on this either, they denied the problem was caused by their plugin