DVR-105 won't burn at 4x help pls

[socrilles]

OK I have tried 4x media certified, 2x media certified, and normal 1x media with the included nero express, and also with record max, in nero express it says that it is recording at 4x but only burns at 1x speed based on time (1 hr + for a disc), while in record max it starts burning at 4x for the first 8% then stops and starts burning at what seems to be less than 1x (have only tried once and currently trying second attempt) on the first attempt it also stopped at 98% and wouldnt let me cancel the burn had to turn computer off because the program locked any1 have similar experiences or know a solution I would really really appreciate it

[socrilles]

I updated the firmware to vers. 1.21 and still no luck, the only other thing i can think of is that I didnt screw the drive into a case so it might be vibrating more than normal could these be the problem? (I put a fair amount of weight on top of it to stabilize it though)