GigaStudio Ensemble 3.1 working fine in standalone mode, as is Cakewalk SONAR 4.03. However, when attempting to use GigaStudio in ReWire mode with SONAR, I get erratic MIDI behavior -- most notes sound, but it's almost like about 30% of the MIDI messages are not getting through (including some MIDI off messages, because I end up with stuck notes).
The problem is occuring with only GigaPiano loaded on a single channel (no convolution). CPU load looks fine, and the issue is there whether I'm playing back a MIDI track or trying to record from an external controller. SONAR is lightly loaded as well (single MIDI track going to ReWire, single Audio Track coming back from GS3).
I am using ReWire MIDI Output, not the GS3 midi drivers, and I have disabled all hardware MIDI input in GS3 itself. I have also eliminated any possibility of endless MIDI loops/feedback on the hardware side.
I had a problem like this using Sonar 2 and Giga 3 in rewire. The problem went away when I adjusted the audio buffers to their lowest numbers. I don't have Sonar installed just now but as I recall it is in the options>audio. There is a # for buffers which I set to 2 and a sliding bar that I set all the way to the left for the fastest setting. Then my problem went away.
However I never had a problem with stuck notes so your problem may be something different.
ok- I actually reproduced your problem unintentionally. In my case it happened using two different computers. My sequencing program was on one computer and it was acting as a midi master to my second computer which had giga. The giga card is a gina3 and I was using low latency midi drivers with it. In this situation, I had the same problem that you had. When I switched the gina to the regular midi drivers the problem went away.
I haven't the foggiest if this applies in any way to your computer.