That's the problem - you have more RAM. The caching routine is designed around the normal 16MB. It is extremely aggressive, in that it completely tries to fill the cache each time. The issue is that it performs the disk reads and buffers the data into the kernel memory space, flooding out other processes. While memory support was added to the 2.01 kernel, there were no known changes to the caching mechanism. Thus the aggressive caching tuned to 16MB becomes a psychotic serial killer with 64MB.

The error you are seeing might be another symptom of this memory limitation. Question - do you notice the same behavior if the player is paused? This is just a test to see if it is the cache (assuming that the paused player fills the cache and then rests once it is full) or the player application in general.