Hi,

   I don't have a Mac, so I probably won't be of much help, but I saw you weren't getting any replies so I just thought I would offer the possible things I can think of (all of which you might have already tried, so forgive me in advance ):

First, I have noticed Mountain Lion users have been having problems with crackles and other noises etc. and also devices not working - here are a couple of pages:

http://line6.com/support/thread/88571?tstart=0

http://line6.com/support/thread/86574?tstart=0

Second, (though I am pretty sure it will be due to Mountain Lion and not this) you could have a look at the usb info page at:

http://line6.com/support/docs/DOC-4282

Having said that about it probably being Mountain Lion related, I have just seen a post from a pre-mountain lion mac user who couldn't get it to work, although it didn't seem to be when pod farm was opened.

The third thing is to possibly contact technical support by going to the top right of this page in 'support' and then clicking contact technical support, and also contact technical support on the page after that.

Sorry I can't be of much more help.

God Bless,

David

Hope some fix comes for you and the other ML users.