I have a kind of a problem... Basically, I am not asking this time for help to solve that, but I am trying to understand what is happening. Please read the facts:
I am writing in SX and GigaStudio an orchestral piece. It has lots of midi tracks and a few audio tracks. I have recorded the audio tracks in the first place, which were in time with the SX metronome. I then played the midi tracks, which sounded most of the time in time, but they needed a bit of quantize. So, I quantized them...and all of the notes sounded a bit late. I undo-ed the quantization and openned the key-editor. All the notes were about 35ms early in the recording. (I had set the ULLI at the lowest value at 48KHz).
In the beginning I thought it was that midi early-note timing issue that some experience with SX. But all these people who had experienced that, their recording were up to 1 bar early or late, whilst mine were only 35ms. Furthermore, the solution to their problem was installing XP as "standard pc" and disabling the emulated ports. I had already done both. So, I though this is not the case.
I thought then that maybe the audio is out of sync with the midi (i.e. the metronome). I routed the metronome audio into SX again and recorded it to see if this is the case. The metronome recording was sample accurate! So, this is not the case.
I then thought that maybe the latency is because of the GSIF drivers. So I routed GSIF to ASIO and did 2 test recordings with a percussive sound to test the latency. With the lowest ULLI setting (23ms if I remember), the ASIO recording of a midi note which was exactly on the beat, had a latency of 1280 samples. (=27ms)
When I did the same thing with the highest latency setting (3ms) the ASIO recording was 150ms late. (=3ms)
So, it seems that the ULLI setting affects the GSIF latency too. But them.... no matter what is the ULLI setting, I dont notice any difference when I play live in GigaStudio (the response feels immediate).
What is happening here? Can anybody of you understand? I dont get it... Is it SX? Is it Giga? Is it the GSIF drivers? Is it the routing in SFP?