problem accessing cd writer on Optiplex 760

[Mark Davies <mark%ecs.vuw.ac.nz@localhost>]

Hi,
   If I run k3b (kde cd/dvd burning software) on a Dell Optiplex 760 
with no disk in the optical drive I get this:

 cd0(ahcisata0:1:0): passthrough: adapter inconsistency

printed on the console and the k3b process hangs.

On an equivalently configured Optiplex 755 or 745 no message is 
printed, process doesn't hang and k3b reports "no medium present".

If I have a disk in the drive when k3b is run then all three report 
the correct info for the drive.  This is with 5.0_RC3.

Any suggestions how to track down/fix  what's going wrong with the 
760?

dmesg for the 3 machines follow:

760
cd0 at atapibus0 drive 0: <TSSTcorp DVD+/-RW TS-L633A, , D300> cdrom 
removable
cd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 
(Ultra/100)
cd0(ahcisata0:1:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 5 
(Ultra/100) (using DMA)

755
cd0 at atapibus0 drive 0: <PBDS DVD+/-RW DH-16W1S, , 2D14> cdrom 
removable
cd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 5 
(Ultra/100)
cd0(ahcisata0:1:0): using PIO mode 4, DMA mode 2, Ultra-DMA mode 5 
(Ultra/100) (using DMA)

745
cd0 at atapibus0 drive 0: <_NEC DVD+/-RW ND-3650A, , 105C> cdrom 
removable
cd0: 32-bit data port
cd0: drive supports PIO mode 4, DMA mode 2, Ultra-DMA mode 2 
(Ultra/33)
cd0(piixide0:1:0): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) 
(using DMA)


cheers
mark