I copied the image to a laptop and ran a verify with imageburn against the same disc on the laptop. It came up with no errors.
Here's the log -
I 22:58:41 ImgBurn Version 2.4.1.0 started!
I 22:58:41 Microsoft Windows XP Home Edition (5.1, Build 2600 : Service Pack 2)
I 22:58:41 Total Physical Memory: 1,538,480 KB - Available: 758,168 KB
I 22:58:41 Initialising SPTI...
I 22:58:41 Searching for SCSI / ATAPI devices...
I 22:58:41 Found 1 DVD-ROM and 1 DVD-ROM/CD-RW!
I 22:59:24 Operation Started!
I 22:59:24 Source Device: [1:0:0] SONY CD-RW CRX830E JPK4 (D:) (ATA)
I 22:59:24 Source Media Type: DVD-ROM (Book Type: DVD-ROM)
I 22:59:24 Image File: F:\temp\IMAGE.dvd
I 22:59:24 Image File Sectors: 3,697,696 (MODE1/2048)
I 22:59:24 Image File Size: 7,572,881,408 bytes
I 22:59:24 Image File Volume Identifier: XBOX360
I 22:59:24 Image File Volume Set Identifier: 33479a57
I 22:59:24 Image File Implementation Identifier: Daikin U.S. Comtec Lab
I 22:59:24 Image File File System(s): ISO9660, UDF (1.02)
I 22:59:24 Read Speed (Data/Audio): MAX / MAX
I 22:59:24 Verifying Session 1 of 1... (1 Track, LBA: 0 - 3697695)
I 22:59:24 Verifying Track 1 of 1... (MODE1/2048, LBA: 0 - 3697695)
I 23:21:13 Exporting Graph Data...
I 23:21:13 Graph Data File: C:\Documents and Settings\Eddie\Application Data\ImgBurn\Graph Data Files\SONY_CD-RW_CRX830E_JPK4_MONDAY-APRIL-21-2008_10-59_PM_N-A.ibg
I 23:21:13 Export Successfully Completed!
I 23:21:13 Operation Successfully Completed! - Duration: 00:21:48
I 23:21:13 Average Verify Rate: 5,653 KB/s (4.1x) - Maximum Verify Rate: 8,008 KB/s (5.8x)
I did have DVD-43 installed, but I turned it off. Also, I have Alcohol installed (although it wasn't running but it has a resident virtual drive). I burned the same image again on the same system and I got the same error in the same location. Also I'm using CA anti-virus and security applications. The error always comes up at offset 49 of a sector and always reads the value of the disc as 0x00 - it never gets a can't read error. Also, it only seems to happens on DVD+R DL discs (never on single layer discs). I was using a patched Pioneer firmware to be able to use bitsetting on single layer discs, but I reflashed the drive with the original firmware before I burned the image again and I got the same error at the same spot.
As there was no error on the same disc when it was verified by the laptop, it appears to be a problem reading the disc which always occurs at byte 49 of a sector, but only happens intermittently. Could an anti-virus program do this?
Thank you all for your advice.