Pioneer DVR-109 burner and problems when burning
 

ok, i have a Dual Layer Pioneer DVR-109 burner that has given me so many problems when burning. I have updated firmware to the latest version. However, no matter what media i use the burner continues to give me burning problems. Verbatim seemed to be the best media but I have used various media like HP, Sony, TDK, Memorex. Now, i use either Sonic Recordnow or TMPGEnc DVD Author's DVD Writing tool to burn dvds. This is what happens:

1. I put the blank dvd in and the drive begins to read the blank disk and i usually wait until the burner is done reading the disk.
2. I load up the folders to burn and then press Burn.
3. Once the process begins, it stalls for a bit and then if i'm lucky it begins to burn. However, i've seen it stall for a minute and then spit out my disk. I usually get an error message and then i have to use a new blank disk. But, if i do get a good burn it sometimes gets stalled when closing the session after it has burned all the data.

So, i would appreciate any help cause I really don't want to waste my money on all these blank disks and then throw them out in the garbage all the time.

Sounds like a dirty burner.