Bulkpaq DVD-R 4X Generation 4 Orange Quality Concerns

Hi
I just purchased a 25 pack of the above media to work with my LG GSA4040B
DVD Burner. However, when I tried to copy a DVD last night using Nero 6 my
burner made a large buzzing noise during the burn but did burn successfully.
This has never happened with any other kind of disc I have burned in this
drive. Plus the disc will not play in either my Philips DVDR880 or my
Toshiba 220E DVD Player but will play in my DVD-Rom drive! It will also
playback on my LG GSA4040B drive but makes the drive buzz. Anyone got any
ideas? Would I be able to take the discs back to the shop and upgrade them
to something better? Any views welcome.
Thanks
Fred.