Fortunately CD-ROMs have the possibility be controlled by software to spin in a number of different speeds. That would enable you to run your 48X drive in 8X. If you are using windows on your pc I know for certain that a number of utilities exists.
Whenever I watch a movie using my PC I use the utility "Nero DriveSpeed" to set my CD-ROM to 8X. There is some software and text about this here:
CD Speed On the amiga I am not so sure if anyone have written a utility like this.
/Patrik
