qjackctl strange sound on iMac 2008 model

Hi, this is my first post.

I am trying to build my studio in linux seeing how my pro tools and interface are too outdated to work with current OSX and Windows systems. I am trying to figure out jack. Whenever I connect Hydrogen or LMMS to Jack Audio I get very little bass, polyphonic distortion, and a strange sound (kind of like a laser sound you would do as a kid) whenever you release a midi note. I am using my internal sound card. LMMS sounds fine when going directly to ALSA but has a latency issue.

P.S. I am very new to linux and don't know that much about command line. I had been trying to use Ubuntu Studio on my iMac but it was too buggy so I had switched to Linux Mint 14. The weird jack sound occurred on Ubuntu Studio as well.