Help With MIDI Latency During Playback & Recording

Hello to all, this is my first official post here in the Forums--long time lurker, short time poster!
 
Anyway, I was hoping someone could help me tweak my Sonar Pro to be more considerate towards external synths. It seems that depending on the project, I get more or less MIDI lag during playback and hardware recording. I have included a screenshot to show what I mean.
 

 
In the screenshot, you see a recorded waveform from an external synth (using a patch with a ZERO attack envelope). Above the waveform is the actual MIDI note, highlighted for clarity by the Now-Time bar. The difference between the MIDI note ON and the start of the audio waveform is about 578 samples @ 48kHz (12ms). This value is not very close to my total ASIO reported round-trip time of only 6.5ms (314 samples).
 
Overall, am I splitting hairs here or should I offset the Record Latency Adjustment to compensate for the delay?  The "LTU Checker" program only reports a difference of 5 samples. Should it be my goal have the audio line up as close as possible to when the actual MIDI note is triggered?  If so, what is the best way to go about doing it?
 
To me, I can actually hear the slight delay. And it seems that the more plugins I add into a project, the worse it may become. I may be able to go down 1 or 2 settings in the Focusrite MixControl software for buffer size before audio starts crapping out in SONAR, but it only makes a negligible improvement. However, at this time, I would rather have the stability of a slightly larger buffer than balls-to-the-wall small.
 
Thanks for any help. If there is anything else that you may need to know for troubleshooting, please ask. I appreciate the responses.
 
 

scook
Are there any plug-ins with look-ahead buffers in the projects? SONAR adds delay to all the tracks to compensate for those plug-ins.

 
Hmm. Not that I know of. Turning on the PDC button actually makes it a little worse.  I just tried it. My current project is more set up for test, with no plugins and the external synth being recorded dry.

jb101
Instead of disabling the PDC, try disabling all effects by pressing "E" on your computer keyboard.

Thanks, jb101. I will give this a shot a report back. Basic question for all regarding the PDC button--is it normally left ON or OFF for most projects?  Seems like Sonar compensates for latencies quite well except for its own LP-64 plugins.

Normally PDC is on. Any plug-in with a look-ahead buffer needs compensation to keep the tracks in sync regardless of the manufacturer. It is also advisable to use those types of plug-ins after tracking is completed.
 
 
Edit: I must be slowing down again. Have to remember to check for posting updates before committing mine.

I don't know if this applies, but I have to go to Preferences | Drivers | ASIO Panel and set a very short number (like 128 or 256) while recording.  I then set it high (like 1024) when mixing with effects like Melodyne.  With a high number, the external synth MIDI is so far behind that I can't possibly record in any reasonable manner.

Thanks for the help, guys. I was able to improve matters by checking the "Use ASIO Reported Latency" parameter in the preferences (see screenshot below).

For some reason, this parameter was unchecked, though the Help Guide reports this is checked by default. Weird. So far, it lines up the audio vs. midi fairly well.  I imagine if I need to get it just a little bit better, I use the Manual Offset parameter, correct? One question on that, however...does it affect the output/timing of MIDI Sync?
 
Also, what exactly does the Playback buffer size adjustment do? Default is 250ms. I've set mine to 100ms but can hear no difference.

One thing I am experiencing, perhaps related, is that when I move MIDI notes in the Piano Roll or loading sysex files into the Sysex window, I get crackling and a big burden on the CPU. Anyone else experiencing this? I can't imagine either of these tasks as burdensome to a quad-core CPU. Sure it's no i7, but come on...we're talking about tasks stemming from the early days!