robert_e_bone
Jim - I would like to add to your list of where latency comes from - external to Sonar, background services / device drivers can also spike latency, such as Wi-Fi adapters, some antivirus software, even laptop battery management - these can all wreak havoc on latency.
 

Hi Bob,
 
We're talking about two completely different things.   

• I'm talking Audio Latency 
• You're talking DPC Latency

You're right that many factors can affect DPC Latency.
To effectively run heavy loads at low Audio Latency... your DAW needs low/consistent DPC Latency.

scook
I don't understand how these external processes directly the affect latency. How do these processes slow the audio signal?

Bob is talking about DPC Latency.
Your DAW does need low/consistent DPC Latency to effectively run heavy loads at low Audio Latency settings.
 
DPC Latency spikes affect the data flow... which would manifest as glitches (at best) and drop-outs (at worst).
DPC Latency spikes themselves don't determine audio latency... but they can affect performance at a given latency setting.  Assuming substantial load, the lower your audio latency... the more critical it is to have low/consistent DPC Latency.
 
Hope that sheds some light...

I understood your reply to Bob. Things get confused when using terms like latency without context. The original post and title are not clear so we are all left guessing until the original poster decides to reply.

I respectfully disagree.
 
DPC Latency spikes (DPC means Deferred Procedure Call, by the way) can and do occur outside of Sonar, even if their occurrence is only noticed from within Sonar, per some of the things I listed in my earlier post.
 
I did not say and am not saying Jim was wrong.  I only added those items to his list, because they too can cause latency issues that manifest themselves in several ways within Sonar.
 
The original poster indicated problems with 'latency', and did not specify whether or not that meant specifically a 'lag', versus other types of issues with latency, such as dropouts/crackles/distortion.
 
Bob Bone
 
 

Does this mean you believe the original post and title have a clear meaning, you are not guessing and the original poster need not reply?

scook - apologies - I am not understanding your questions very well.  (and now I know why).
 
I just removed a giant bunch of text from this reply, because while I had been typing my response to what slartabartfast had posted, Jim and then you had posted, but I had not seen those yet, because I was typing my 'I disagree' post - to slartabartfast's post.
 
Sooooo, when I had finished typing and hit Submit Post, Jim's post and then yours appeared in between, and I never saw them.
 
Sooooooooooooo, you took my 'respectfully disagree' to mean me disagreeing with YOUR post, when in fact I was disagreeing (respectfully, nonetheless) with an EARLIER post by someone else.
 
S0000oooo, I do NOT disagree with you, Jim also cleared up what he was referring to (audio latency), versus my points, (DPC Latency), and I DO agree that nobody can help the original poster until he explains more about the nature of the issues, AND provides more information about his system and current settings, as well as things loaded into his project and all of that.
 
Sooooooooooo - we cool???????
 
Bob Bone :)

And Jim, 
 
Yes, I completely agree with your further explanation.  We were indeed talking about 2 different flavors of latency.  My post was only due to your not specifying audio latency versus latency in general, so I added the DPC latency pieces to it.
 
And, as noted moments ago in my just-posted response to scook, ALL of us agree that the original poster was not at all clear, and that we all need additional information in order to help him.
 
Bob Bone
 
 

Thanks everyone.  I switched to ASIO as opposed to WDM/KS and it seems to have helped allot.  Does everyone hear prefer ASIO ?  Also I seem to have some software synths cutting off notes during playback.  Any suggestions?  
 
Thanks again,
dan 

Everybody prefers ASIO. Increase the MIDI buffer in preferences and then you are laughing...

Yeah, notes can randomly not play and such, with the 'new' default of 250.  It used to be 500, and lots of folks have adjusted that back to 500, with good results.
 
Bob Bone