used mpc2000 freezes during sampling - need help

Hey all. Sorry if this has been posted before... I tried using the search function to find an answer, but I'm just not getting it. I recently got a used but said to be fully working MPC2000 on eBay for about 750 bucks. So far it looks good and as described but I'm having a strange problem; twice now, the machine has frozen up during the recording of a sample. So far I've just tried recording mouth sounds through a mic, and it usually works fine, but with no warning, the machine has done this same thing twice. The seller suggested it might be recording for longer than I expected it to (I'm new to this stuff,) but that is obviously not the problem. The "recording..." status remains, but no sound is recorded, none of the buttons respond, nada. Any ideas guys?

Also, it was advertised as having the memory fully expanded. What is the easiest way to check if this has been done?

I think my seller is on the level, but I need to settle this stuff. Any help would be much appreciated. Thanks!

Eben

Can't help with the freezing problem, but to check the amount of ram installed, just hit 'open window' while in the sample screen .