Adding music to my Galaxy Nexus causes the phone to slow down considerably.

[synthesize-me]

Whenever I add more than 1 or 2gb of music to my 16gb Samsung Galaxy Nexus running 4.2.1, it causes the phone to slow down or lag, often freezing and crashing. I can add music either manually via drag and drop from my PC or sync it with mediamonkey while plugged in or wirelessly, but either way this slow down/lag occurs. Currently there is 9.99gb available of free space on the device with 1.32gb of apps. The bit rate of the music varies but it is usually between 128kbps and 320kbps. Is my phone just too old? Any help would be great.