No audio/No system playback

Hello, i can’t hear recorded audio anymore. This applies to older projects but also to a new project. All routings within Ardour, Jack and System have been checked. The have not been changed since the last time I used Ardour. Did I overlook something else?

Versions: Mac OS 10.6.8, Ardour 2.8.16, Jack OSX 0.89

please get back on IRC and this time stick around for more than 2 minutes.