Disappearing/Reappearing Media/DVD burner

Hello, thanks in advance to anyone who has any insights.

I have a Samsung Writemaster 164 for DVD/CD burning. I have an old HP laptop that I was thinking about replacing, since I've added just about every doggle possible to it, but I'm kind of fond of it now, and the only thing that was missing was DVD burning, so when I saw an inexpensive external burner this weekend, I thought I'd get it and put off replacing the laptop for a year or two.

Anyway, back to the problem. I've only had the burner for a few days, but I've already noticed that the PC has an intermittent problem communicating with the burner. WHEN IT'S COMMUNICATING, everything works great. But at a certain point, I'll put in a DVD+RW disk, and I'll get this "please insert a disk" message (absence de disque, in French, where I am at the moment) if I try to erase, or it will open the tray and ask that I insert a disk, if I try to burn a data DVD.

But here's the weird part. Last night I put the laptop into hibernation when I went to sleep, and when I turned it on in the morning, there was the disk, and I burnt on it with no problem, so I'm 99% sure that this is not a media problem nor a physical problem with the burner. Then later in the day, it stopped seeing it again. I unplugged the USB cable at one point during the day, and replugged it and ... voila, the disk was back. I seem to be able to burn CDs (not DVDs) without problem, and read commercial DVDs (movies) also without problem, but maybe I'll eventually get this intermittent problem with them also. I'm pretty sure that this has something to do with a driver conflict or an XP problem. FYI, I'm pretty computer competent, but I tend to get lost when someone starts throwing around too many letters (IDE, APSI, DMA).

Other facts:

* Nero 6 (came with DVD burner)
* USB connected through a PC card for USB 2.0
* updated firmware yesterday
* also connected to laptop - external HP cd-writer 8200
* older nero and easy cd creater were on laptop before I bought the DVD burner, but I deleted them and ran the roxizap tool
* didn't install InCD (came with burner) since I'd read evil things about it

Lastly, here's the log file (rather short) from one of the failed burn sessions from Nero. It's short because (like I said earlier), if the communications are working, it burns with no problem, but if not, it fails right away (asks for an empty disk).

Windows XP 5.1
IA32
WinAspi: -
ahead WinASPI: File 'C:\Program Files\Ahead\nero\Wnaspi32.dll': Ver=2.0.1.74, size=164112 bytes, created 26/10/2004 17:35:32
Nero Version: 6.6.0.17
Internal Version: 6, 6, 0, 17b
(Nero Express)
Recorder: <TSSTcorp CD/DVDW SH-W162L>Version: TS03 - HA 3 TA 0 - 6.6.0.17
Adapter driver: <> HA 3
Drive buffer : 2048kB
Bus Type : via Inquiry data (1) -> ATAPI, detected: ?
Connected to MMC as unknown drive with class-nr : 1
Drive is autodetected - recorder class: Std. MMC recorder
CD-ROM: <MATSHITA DVD-ROM SR-8175 >Version: G035 - HA 1 TA 0 - 6.6.0.17
Adapter driver: <atapi> HA 1

=== Scsi-Device-Map ===
DiskPeripheral : SAMSUNG MP0603H atapi Port 0 ID 0 DMA: On
CdRomPeripheral : MATSHITA DVD-ROM SR-8175 atapi Port 1 ID 0 DMA: On
: HPUATA Port 2 ID 0 DMA: Off

=== CDRom-Device-Map ===
MATSHITA DVD-ROM SR-8175 D: CDRom0
MATSHITA DVD-ROM SR-8175 E: CDRom1
TSSTcorp CD/DVDW SH-W162L G: CDRom2
=======================

AutoRun : 1
Excluded drive IDs:
WriteBufferSize: 40894464 (0) Byte
ShowDrvBufStat : 0
BUFE : 0
Physical memory : 255MB (261616kB)
Free physical memory: 55MB (56444kB)
Memory in use : 78 %
Uncached PFiles: 0x0
Use Inquiry : 1
Global Bus Type: default (0)
Check supported media : Disabled (0)

1.11.2006
Compilation ISO
22:40:48 #1 Text 0 File Isodoc.cpp, Line 6356
Iso document burn settings
------------------------------------------
Determine maximum speed : FALSE
Simulate : FALSE
Write : TRUE
Finalize CD : TRUE
Multisession : FALSE
Burning mode : DAO
Mode : 1
ISO Level : 1 (Max. of 11 = 8 + 3 char)
Character set : ISO 9660
Joliet : TRUE
Allow pathdepth more than 8 directories : TRUE
Allow more than 255 characters in path : TRUE
Write ISO9660 ;1 file extensions : TRUE

22:40:48 #2 Text 0 File Reader.cpp, Line 127
Reader running

22:40:48 #3 ISO9660GEN -11 File geniso.cpp, Line 3309
First writeable address = 0 (0x00000000)

22:40:48 #4 Text 0 File Burncd.cpp, Line 3233
Turn on Disc-At-Once, using DVD media

22:41:01 #5 Phase 40 File dlgbrnst.cpp, Line 1832
Aborted by user

22:41:01 #6 Text 0 File DlgWaitCD.cpp, Line 282
Write in overburning mode: NO (enabled: CD)

22:41:01 #7 Text 0 File DlgWaitCD.cpp, Line 2483
Recorder: TSSTcorp CD/DVDW SH-W162L
Medium not present

22:41:01 #8 Text 0 File DlgWaitCD.cpp, Line 448
>>> Protocol of DlgWaitCD activities: <<<
=========================================
Insert empty disc to write to.
(Medium in drive: Inconnu. Medium required by compilation: DVD+R/RW; DVD-R/RW; DVD-R DL; DVD+R DL.)


Existing drivers:
File 'Drivers\PXHELP20.SYS': Ver=2.03.28a, size=20640 bytes, created 01/08/2006 22:48:02 (Prassi/Veritas driver for win 2K)
File 'Drivers\atapi.sys': Ver=5.1.2600.2180 (xpsp_sp2_rtm.040803-2158), size=95360 bytes, created 04/08/2004 06:59:42 (Adapter driver for src)

Registry Keys:
HKLM\Software\Microsoft\Windows NT\CurrentVersion\WinLogon\AllocateCDROMs : 0 (Security Option)