... and if it's NVidia NForce, you might need to get a new computer ... or at least a new mainboard, which often amounts to the same thing.

At least this was the case for me. I had a Core 2 Duo computer ... good specs, and it should not have any latency issues. But I always had latency issues, and I could never find the cause. But earlier this week I noticed an odd thing: The latency issues (dropouts, crackles etc.) would cease or at least diminish when I minimize the recording application window. It seems like the more was going on visually, the more latency problems there were.

Long story short: A few days ago I upgraded to a new mainboard, and all the problems are history. Well, not all of them, since I also upgraded from Vista to Windows 7, and now the KB37 is kaputt, but obviously that's a different problem. As far as latency is concerned, the NForce chipsets (or at least the one that my old mainboard had, I guess it was an NForce 6) appear to cause timing problems on the PCI express bus that can cause problems for realtime applications using hardware connected through the PCI bus (and I guess that USB hardware is also connected internally through PCI lanes).

So my question to Line 6: Are you aware of that problem? If so, telling me would have spared me a year of misery.

And to anyone else: If you're also experiencing latency problems, Make sure you check your mainboard chipset - if it is the cause of the problem, none of the usual tips to achieve low latency will help.

BTW: I'm currently not using Line 6 hardware to record - I'm using the ESI Maya 44e interface, and I can use it at 48 samples, achieving 2ms roundtrip latency with Guitar Rig 4. As soon as Line 6 manage to get the KB37 working properly in Windows 7, I'll try it there, too, and I guess that 128 samples won't be a problem (too bad that the Line 6 driver *prevents* lower settings). But I wouldn't use it for my recordings, since the ESI Maya 44e has a much better audio quality than the KB37.