Cubase SX3, an ASIO-compatible host application, allows only one driver at. Generic multi-device drivers that allow several completely different interfaces. The on-board sound chips found on most PC laptops with low-latency ASIO support.

We have had interesting problems with this. Let's speak english comic. What we were told to check was teh Buffer Size Samples settings.

We have Cubase SE so I'm not sure if it is in the same place but we go to: Devices > Device Setup >VST MultiTrack (in the left side bar) Make sure 'ASIO Multimedia Driver' is chosen NOT DirectX option Then click: Control Panel > Advanced Options Douible click teh number under the Buffer size and set it to what you want. We were told 540 is an ok number. Do this for Input and Output. Click apply and Ok as many times it takes to get out.

Don't worry about the test it asks yout to run. You can do it or click no. Once set it seems to persist for all users on that machine. Hope that helps. What spec are the PCs. If I understand you correctly this problem isn't an audio latency problem (ie the placying back of VST instruments sounding late after you press a key) but with midi notes in the editor being either very early or late in comparison to when you actually played them. We had this problem on a couple of PCs but I can't remember if we were using VST5 or SX3 at the time, and there were a lot of people struggling with this in the Cubase forums at the time.

I found a cure that worked great for us. I went into the BIOS and altered the CPU settings from automatically configured to manually configuring the Speed/Multiplier for that processor (It was an Athlon of some sort).

Once it was set manually the midi timing issues vanished. Don't ask why as I've no idea, but it did cure the problem.

Also if using external devices with ASIO drives, Cubase will some times revert to other ASIO drivers if the device has been removed and replaced, a quick work around was to actually remove all other ASIO drivers than the ones for the sound card. Worked very well. We now have a Sibelius suite and use the ASIO4All driver to combat the latency issues (our music teacher says it's ok but deep down i know it isn't.) TBH tha ASIO Multimedia Driver is crap and has massive latency issues when recording audio. ASIO4All is better but not the best. You say you have 'decent external soundcards' try completely disabling all other sound cards, and make sure you have updated the firmware recently and are using the correct ASIO drivers (a computer i regularly work on has 10+ ASIO drivers installed as i take different interfaces depending on what i'm recording - the on-board soundblaster has 4 on it's own). Another thing to watch out for when using USB keyboards is that you ither have the manufacturer specific drivers for them or use the windows one. Our keyboards have a switch on the side to select what they appear to the host as (i found the windows ones to be better than the edirol ones!!!).