I'm doing some troubleshooting on a disc that for some reason is nearly unreadable on all my Plextor drives (despite it being in what appears to be perfectly fine condition). It dumps just fine with Alcohol on my LG drives, but the PX-760A and both the PX-716AL drives just rattle and can't read it. The Premium can read it, but it struggles a lot and often crashes DIC.
The disc is a copy of the PC game "Rollcage." I found it second hand ages ago, and I don't even know what region it is. It indicates on the disc that it's in English, so it's probably not a North American release (most of my CDs are), but it also doesn't seem to match the Europe copies in the database. It has 9 tracks like the ASUS OEM release, and the data track matches, but none of the audio tracks match and the mastering ring / serial is different.
I was finally able to get a dump from the Premium. Since it struggled severely, I wanted to be paranoid and check the dumped audio against what the LG dumped using CUERipper. So, I converted the first audio track from CUERipper to raw signed 16 bit audio (via ffmpeg), and I opened up both the DIC bin output of the first audio track and my converted file in HxD. Based on the leading zeroes in both files (as seen in HxD), I used the hex editor to manually adjust the offset in the CUERipper track to match the DIC one. I also truncated the CUERipper track to the length of the track output by DIC (the lengths of the tracks were different both before and after padding to correct the offset). After that, the files matched (compared with fc.exe).
Cool, looks like probably the first audio track was dumped correctly despite the Plextor's struggles. So I move on to the second, expecting to go through the same set of steps. However, when I load up the second audio track from DIC in HxD, there's obviously samples from the first audio track at the beginning of the second one, before the 2 second silence. Importing the raw audio in Audacity shows that, indeed, there's a very short click of audio on the track before the 2 second silence. The CUERipper files don't seem to have any of this overlap (but it looks like there's instead overlap of the pregap).
I expected the offsets to be different between CUERipper and DIC (though, honestly, I'm not sure why except I gather it has something to do with offsetting the audio relative to the data track, whereas CUERipper is just concerned with offsetting the audio samples so that it matches other drives when dumping audio data). However, I didn't expect to find samples from the end of the previous audio track at the beginning of the next. Is this normal? Is it something I need to investigate further, or is it maybe just a common mastering error where some number of samples are misaligned?
Forgive me if this is an extremely obvious question to the more experienced rippers, but I've been dumping PC games and relatively few of them have been "enhanced" CDs, so I haven't looked into it previously. I may try to follow the old dumping guide to see if I get the same results as DIC (http://wiki.redump.org/index.php?title= … acks_(Old)), but all the images in the guide are dead so some of it isn't entirely clear to me.