Garageband 11: lagging or unresponsive interface; frequently crashes; and is using way too much memory

Question

Since updating to the newest version of Garageband I've noticed a distinct slow down in interface and functionality; makes editing incredibly difficult having to wait 2-3 seconds after selecting a note or section; sometimes the whole app becomes unresponsive or just crashes altogether. It also completely maxes out memory usage (8GB!) My machine specs are below but I can't imagine why I couldn't run it. It boots up in about 5 seconds and before Mavericks I could run Logic, Garageband, MS Word, Adobe Edge Animate, and Adobe Muse without it breaking a sweat. Now it's running the fans at full blast using way more memory than is necessary.
My Machine
The OS and Applications run off of a 120GB SSD and instead of an Optical drive I use a data doubler and a second internal (500GB HDD) for backups and extra storage - neither are anywhere near capacity.
Also, I'm not running any other apps, and even tried disabling network connections; no change at all. I do know that Mavericks uses memory differently (don't fully understand the benifit or how it works) but when I open Activity Monitor while running GarageBand it show's my "Memory Used:" at 7.99GB/8GB; but the pressure is still in the green. Could someone please explain to me how the memory usage differs now and why my machine needs to use all of the memory at once to run GarageBand when it is the only app open?
Why is it that 10.9 is substantially more taxing than 10.8 while claiming to be the opposite? What am I missing here?
Please Help! :-)

Answer 1

Since updating to the newest version of Garageband I've noticed a distinct slow down in interface and functionality;
Your question is a bit ambigious - the "Newest version" would be GarageBAnd 10.0.1, but the title of your question says GarageBand '11. Are you saying, you upgraded to GarageBand 10.0, but now GarageBand '11 (version 6.0.5) is having troubles?
makes editing incredibly difficult having to wait 2-3 seconds after selecting a note or section; sometimes the whole app becomes unresponsive or just crashes altogether.
Perhaps a crash log could help. Or error messages from the Console window. Does the Console.app show any diagnostic messages, when this hanging occurs?
and before Mavericks I could run Logic, Garageband, MS Word, Adobe Edge Animate, and Adobe Muse without it breaking a sweat.
Have all these applications been updated to the latest, Mavericks compatible versions? And all other non-Apple applications?