converted vob files play on computer fine..skip when burned to dvd

[cduval04]

hi i have some avi files that i ecncoded to dvd files (ifo, bup, vob) when i put it in my dvd player it skipped and the picture got all blocky (some of the blocks were green) but then i looked at the oringinal avi files and the vob files on my computer and they both played fine, so it must be somthing in the burning process right, becuase they stay in vob format when burned to dvd...I am burning a dvd-r at 2.4x becuase I have an old dvd player so i fgured it would be better to burn slower) any ideas whats going on in my burner that makes the picture all blocky and stuttery like that??

I attached a picture of my tv on pause so you could see what the blocking looks like....you cant see it that well though

[cduval04]

i tried burning the same dvd with a different buner and it seems to be working ok so far (i am watching it now) no blocking.....what do you think is wrong with my other dvd burner...do you think the lens leeds to be cleaned?...how would i do that?? its an external Cyberhome 16x DVD+R/RW dual layer burner model EX162E-A any ideas what could be wrong with it..does anyone else have or know of problems with this model....any suggestions would be appreciated