A weird one:
I thought I had a bad DVR-109 until I tested with 40 pins cable (to solve a DVD+RW overwriting bug: now solved by latest firmware).
If DVR-109 is master (alone) on a 80 pins cable, CDSpeed shows abnormal graphic (PCAV) as you can see in the pictures below. First one is Via4.56 drivers (similar graph with Via 4.40) and second one is MS Standard Dual IDE controller. This is with a Mitsumi 4x DVD+RW.
When testing with standard 40 pins cable, Pioneer revert to UDMA33 and the graph is normal (CAV). Same thing with multiword Dma Mode 2 and PIO4. The third graph shows the evidence.
To be sure, I swapped the 80 pins cable to another one, thus eliminating the possibility of a bad cable. No change.
I tried the Via miniport drivers. No chance, CDSpeed won’t run with them so I don’t know if the transfer rate is ok or not.
The only thing I can do now is let the Pioneer on standard IDE cable but I would like to be able to gain the full UDMA4.