[quote=Ibex;2229273]I think Drage ment to say that Lite-On DVD writers can only perform the TA Jitter test on DVDs.[/quote] No, I meant to say what I said.
TA Jitter as currently implemented by CDSpeed is a test for DVD media, not for CD media. It will only run and produce meaningful results on some LiteOn DVD burners (e.g. 5S, 6S, 20A1, 20A4 series).
The TA Jitter tab will be visible if you have a LiteOn CD-RW or DVD burner in your system, and you will even be able to start the test with a CD in your drive, but the result will be meaningless for anything that is not a recordable or rewriteable DVD (a DVD-ROM will make the test fail with [I]Incompatible Medium[/I]).
If you run the TA Jitter test on CD media in a LiteOn DVD burner (not CD-RW burner) you might get a graph that might be meaningful, but even then the calculated DC Jitter will be zero and thus meaningless.
If you run the TA Jitter test on CD media in a LiteOn CD-RW burner, you sometimes get a weird looking graph and sometimes no graph, but the graph, DC Jitter and Peak Shift are entirely meaningless.
I’m not sure about running the TA Jitter test on LiteOn Combo and DVD-ROM drives since I don’t have any.