I noticed right away that the innermost burn position (lead-in?) is closer to the hub on all DVD-R Pioneer 109 burns. At first I was not concerned, but I've noticed several issues that are fixed by merely using DVD+R (which does NOT exhibit the odd burn rings).
The XBOX will not read the discs marked "bad" in the image above. Neither will UDF-only mode files on the LG DVD-ROM in my system. It is a direct issue of DVD-R and only on this drive. I wager this is all related.
Luckily, DVD players with DVD-Video are fine, as are all ISO and ISO/UDF data burns.
I have tested this on the A09XL on fw 1.09 and again on the 109 on fw 1.01. Same results on all tests.
DVD-R used includes MCC01RG20, MXLRG02, PRODISCF01 and TYG01
DVD+R used includes cheapo crap OPTODISCR04 (that I got for free).
On the upside, all the OPTODISC +R burned good so far.
None of my other drives (past or current) ever had this sort of error.