I’m posting this here since it might be useful in case if someone have experienced similar problem.
My Ardour project (soundtrack for animation) got screwed up recently - for some reason it’s stopped playing the sound at certain places - it was giving the nasty short “trrr” noise (like happening when you disconnect headphones) and then silence. I have a daily backup, so I have restored the previous version, but that didn’t helped - the problem remained the same.
After a long investigation I found the problem today - during the last system update I’ve got Calf Compressor plugin (which was used in the project) updated and for some reason it didn’t read the previous settings correctly. The same problem happened with Calf Reverb. I have removed the plugin and inserted it again - now everything works. I’m happy, since I don’t need to re-do the all sound editing from scratch.
My system: Fedora 18 x86_64, Ardour2.
I also tested the buggy project with Ardour3 - the project opened, but in this case there was no sound at all.
I hope this helps.