I have a Marantz CD6000 KI CD player and have come across some CD-R music discs that won't play on it, either it'll display an error reading disc message or it'll play the first track and sorta crash. However, I have four that play absolutely fine, no problems what-so-ever, all discs (including one's that do and don't play) were recorded on the same PC, using the same software (Nero 5.5). In terms of disc makes, three of the one's that do play are 'Discplanet' and the other is unknown, all the one's that don't play are 'Infiniti'. Now I have looked at the discs and have noticed that the discs that do play have a slightly darker underside (the data side), dark green, while the ones that don't play are much lighter in colour, think silver colour with a very faint greeness too them. Could this be the cause of the problem, or is it simply down to my Marantz CD player being picky about different makes of CD-R's? All discs are CD-Rs, all finalised, no CD-Text, recorded at 48X using 'disc-at-once' method.