Pioneer 107 / external carriage problem



ok theres nothing wrong with the 107, it works in a mates duplicator / pc, but as soon as it goes in the external carriage it will burn one out of every 15 discs, it reads fine etc, but on burning it fails…alot.
tryed all different software, tryed using the drivers for the carriage that came on disk, tryed it on 2 different pcs, still no joy, thinkin its to do with the carriage, but is there anything i can do before i take back???

this aint even mine, just trying to sirt it for a mate :frowning: