I think I've finally figured out what was going on with these discs. They're all used now, and I definitely won't buy them again- so this is mostly a warning regarding varying quality.
It looks like there were 2 different lots in the 10-pack I bought and this results in the wildly differing error counts encountered. The serial numbers printed near the centre are all very similar and look like this:
- Code: Select all
E105L A 2 0301261132-667796
E105L B 3 0301261153-668155
The 4 disks with an "A" at pos. 6 were good- independent of the burn speed (nos. 2, 4, 7 and 9 see
previous post). The "B"-disks all show a massive increase in error rate at ca. 44 minutes- again independent of the burn speed. This also shows up as damaged sectors in CD Speed. The scans shown in
verbatim cdr/rw vary in quality are actually typical for the "A" and "B" lots and it was pure coincidence that the bad lot was burned at 48x at that time !!
So the final verdict is:
- "A" lot >= 40x
- "B" lot < 24x, probably damaged at any speed.
Since these came in the same package and there's no way of knowing how the next lot turns out, I can only reiterate: avoid them!
G