Years ago I created many projects using ancient versions of Cakewalk Audio, and never had any real problems. A few weeks ago I purchased Sonar Artist and started to get to grips with the user interface which I find more complicated than in the old days, but I am getting there gradually. However I have encountered a problem that seems to defy explanation. It occurs when using Sonar on my laptop, and its built-in Realtek HD Audio - yes I understand the limitations of this, but please bear with me and read on.
 I open Sonar, and load one of the demo projects, “Sophia Jane – Living For Now”, which has 12 Audio tracks. This plays without any detectable audio problems.
 I now open a new blank project. I create a single audio track into which I import a stereo .wav file “Mysong”. When Sonar tries to play this, there is a constant loud crackle, and the movement of the vertical time line across the screen is quite jerky. There is nothing wrong with the .wav file itself – it plays fine using any other application, and I get exactly the same problem importing any other .wav file including the ones from the demo project. Now (this is the really strange bit) if I add an EMPTY instrument track (TTS-1 Synth, output set to the Realtek Audio), “My Song” now plays without any problem
 
I now open the demo project, and add a new audio track to the twelve already there. I select this track and import the same “Mysong” stereo.wav file. If I now set this track to “solo” it plays without any problems. But if I start deleting the existing demo project audio tracks one by one, the playback of “Mysong” starts to deteriorate, the more demo tracks I delete.
 
WHY?

Hello,
 
Very odd. What are the parameters of the .wave file. (Sample and bit depth) in comparison to the same preferences in Sonar?

Sounds like maybe sample rate is different on the imported wav's than what your default project is set to and your system is choking on the conversion. I had a similar problem in Ableton where I bounced some stereo mixes in 48k and some time later imported them for mastering into a new project which was defaulted to 44.1. I had exactly the same problem you are describing and it took me forever to figure out what was going on. When I set the new project to 48k to match the imported waves, everything was fine.

Edit- I missed the last paragraph and that is indeed strange. I can't think of any explanation as to why adding an instrument track would have any positive effect on your audio playback or why reducing the workload would have a detrimental effect.

Thanks for your comments so far. My imported .wav file is 44.1 and 16-bit (same values as the default project is set to). I notice that the .wav files in the demo (which plays OK) are 24 bit. I am sure the Realtek HD Audio is involved somewhere in this problem because everything is OK when I use my Behringer USB interface, but I don't want the hassle of setting that up when I'm just experimenting rather than doing serious recording. Like dnelson1971 I am completely baffled why adding an empty instrument track makes it work. By the way I discovered that adding a midi-only track doesn't work - it has to be an actual instrument with the output assigned to the Realtek HD Audio, so I don't know if that provides any additional clues.

What driver mode are you using with the reaktek? There are issues with wasapi/wasapi exclusive mode on certain systems that can cause the behaviour you describe. 

Yeah, my laptop freaks out if I don't use my external sound card...it runs out of memory, tryin to process the crap realtek or something?..and plus I had that problem when I 1st started on cakewalk music creator 6 a few years ago, with havin the wrong sample rate etc, I cant remember what I had, but everything was in slow motion and crackled, and of course I blamed the software.......cakewalk customer service saved the day!!!

tenfoot
What driver mode are you using with the reaktek? There are issues with wasapi/wasapi exclusive mode on certain systems that can cause the behaviour you describe. 

^^^this
 
fwiw, i use the onboard realtek in the same situation as you (can't be arsed setting everything up) and use the asio4all driver without issue
/hth

Up to now I was using the WDM/KS driver. I believe I did try WASAPI exclusive, and it didn't work at all. However I've just tried WASAPI shared and now everything seems to be OK. I notice the effective latency has shot right down as well, so I'm even happier! If I get any more problems I may try ASIO4all as suggested, but I'll leave well alone for now. Thank you all for taking the time to comment. 
 
PS I'd still like to know how adding an empty instrument track could make such a positive difference in WDM/KS driver mode!

stevecase19
PS I'd still like to know how adding an empty instrument track could make such a positive difference in WDM/KS driver mode!

seems like a bug?

stevecase19
Up to now I was using the WDM/KS driver. I believe I did try WASAPI exclusive, and it didn't work at all. However I've just tried WASAPI shared and now everything seems to be OK. I notice the effective latency has shot right down as well, so I'm even happier! If I get any more problems I may try ASIO4all as suggested, but I'll leave well alone for now. Thank you all for taking the time to comment. 
 
PS I'd still like to know how adding an empty instrument track could make such a positive difference in WDM/KS driver mode!

Wasapi shared is generally fine for playback, and also recording on some devices. If you run into trouble when tracks are armed for recording, pwalpwal's suggestion to try asio4all is a good one.