Yep, definitely the changer's fault, not your burner or the CDR's. There are just some drives and players that do not like certain types of CDR's, my DVD drive, for example, will not recognize older Memorex CDR's, but now that Memorex uses a different dye, it will take Memorex CDR's. The best CDR's I have found for compatability are Imation, but that's just my experiences. Try a different brand of CDR, or if all else fails get some of the Kodak Gold CDR's, they are supposed to be the best from what I hear.
Zenmervolt