The discs are protected and you complain that you rip them at 4x ! ? ! ?
You're lucky that you can read them.
If they are CDS200 discs, the drive might slow down when ripping due to the errors mastered in the disc. This would be the clever thing to do if the drive is well designed.
Try EAC in burst mode or Feurio to check the real max. ripping speed of your drive.