Hmmm. I installed two more optical drives. All three behave differently.
drive 1: Does fine until the last 4 tracks when it quickly dives to 0.1x speed. Also, on one troublesome disc it completely fails to read the last track.
drive 2: Does fine until the last track when it quickly dives to 0.1x speed. On that troublesome disc it actually crashes Media Center when ripping the last track. (It does it ever time.)
drive 3: Does fine for the first half of a cd. Slows down to about 1.5x for the last half of the CD, but never goes below 1.0x. It is able to rip all tracks on the troublesome disc.
I'm sticking with drive 3 simply because it seems able to successfully rip every cd without ever going below 1.0x. Theoretically I could get greater speed by ripping all but the last 4 tracks in drive 1 and then ripping the last 4 tracks in drive 3. But, that's too much disc switching for me.
I'm trying to rip the discs for 4 different unabridged audio books that I just bought. At this rate it is going to take a VERY long time to rip all the discs (there are something like 100 discs total). I'm tempted to go to the store and buy one of every optical drive in the store and just try all of them.