iMac 27-inch, Late 2009, OS X version 10.8.1, Toast version 11.1 (1067).
I saved a bunch of 44.1KHz, 16 bit AIFF files from Audacity (I recorded LPs at a much higher bit rate then exported to 44.1/16). Added 20 of these tracks to an audio CD and started a burn. Toast hung at "DAO filling the RAM Cache...100%". I pressed cancel, it asks whether I want to stop or continue burning, I clicked continue...back to hanging, i clicked pause and stop, and now the spinning cursor of death.
Next I tried saving my CD as an image file and copied the image file to a CD. This seems to be working.