DVD Burner Problem

i have a Sony DVD RW DW-U18A and its being giving me problems lately. i recently bought 50 pk spindle RITEK. i burnt my first backup and it worked then i want to put and back up on the second dvd disc, it starts to make scratching or screeching sounds after ive placed in the disc. i tried putting the 3rd, 4th,… and it did the same thing. i also brought the dvd discs that didnt work on my burner to my friends house and it work normally. the auto play showed saying what to do but mine didnt even do that just the screeching sounds. is there a problem with the burner? many thanks in advance.

Please don’t cross-post (the same problem in different areas).

This thread closed: please continue in the other which already has replies:

http://club.cdfreaks.com/showthread.php?t=187788