@KennyR
My Yamaha CD-R/W drive does this on some data disks but not others. It's an awful sound and, just as you said, the data rate is terrible when they do this. There is a pause in data transfer while the drive speeds up to maximum speed and then spins down again to read/transfer the data. When you're transfering a huge batch of MP3s or FLACs, it just isn't fun. :-(
My Pioneer DVD-AO4 doesn't have this problem at all but then the CD read max speed isn't as high; I think it's on the order of 16x.
I guess I'll be trying that Plextor CD-R/W sooner than later. I hate the noise that the Yamaha makes when it spins up, though it has been a super-reliable drive and hasn't burned a coaster yet.
