I've been recording with Sonar for some 26 years.  I cannot remember the last time I had an audio issue.
But now I do.  I included a link to a sample of the problem, a short mp3 file.
I've tried raising my audio buffers to 1024, I always keep them at 512. 
I've tried deleting the aud.ini file and starting Sonar so it can create a new one.
I've tried recording from a soft synth running under Sonar and recording a MIDI track from my external VSL library computer, but it doesn't seem to matter the source, the problem is still heard.
I've tried lifting the i/o disk read/write from the default 256 to 512.
I have the latest MOTU audio drivers for the 1248.
I am running Sonar Platinum 2007.3 (released in March) and have Windows 7 with 16GB of RAM
and 2 fast HHD drives.
 
Here's the problem:  http://www.jerrygerber.com/mp3/test.mp3
Little audio crackles are heard throughout the recording. 
 
Thanks for helping me to resolve this!
 
Jerry
www.jerrygerber.com
 
 
 
 

if nothing has changed and this problem came out of the blue I suspect something very obvious and not too trivial.
I would start by unplugging devices and power down and reboot.
Then I would power down all devices for a minimum of 30-60 seconds.
 
Check to make certain your driver mode hasn't changed.
I have had similar issues in the past where a cable to my interface and also once a bad USB port.
Where my devise would work but had static, drop outs, Noise similar to wireless interference.

It sounds like digital clipping to my ears. Check all gain stages and then check them again ;)
 
CJ

CJaysMusic
It sounds like digital clipping to my ears. Check all gain stages and then check them again ;)
 
CJ

Normally I would agree, however clipping is an ugly sound. This sounds more like wireless interference, a bad cable, a USB port going array.

CJaysMusic
It sounds like digital clipping to my ears. Check all gain stages and then check them again ;)
 
CJ

I've checked my entire signal path, and cannot find out where any gain stage is clipping. All my metering is showing normal recording levels.  I'll check again.
 
Thanks,
Jerry
 

That chirping is also what you would get from placing a cell phone too close to a speaker phone before the "star phones" received mods to eliminate it. Do you have any portable transmission devices anywhere near your cabling/physical signal path?

If its not your cables and its not clipping, then it could be an IRQ conflict.
 
Or you could have some sort of effect on the clip level that you cannot see, like an Vinyl effect.
 
CJ

My mouse did this. I went and got the driver from logitec and the problem hasn't returned.

mettelus
That chirping is also what you would get from placing a cell phone too close to a speaker phone before the "star phones" received mods to eliminate it. Do you have any portable transmission devices anywhere near your cabling/physical signal path?

No, I turned off my cell phone and disabled my wireless internet connection.  Also swapped out my USB cable for a new one and tried a different USB port.  I also updated Sonar to the latest version and deleted my aud.ini file and reopened sonar.   I am now updating Windows, but I doubt that's the issue as my updates are pretty up-to-date and missing only 3 files.
 
I've tried turning everything off and rebooting.   crackling still there.   It's not clipping, doesn't sound like clipping, clipping is different  Perhaps the 1248 has a hardware problem (it's only 3 months old). 
I'll try a new mouse driver but I doubt that is the problem.
 
Crapola!!!   This is really slowing me down...
 
I'll call MOTU on Monday. 
 
 

Not clipping.
At what appears totally random points, the waveform gets pulled to zero for between 1 to 6 samples before recovering.
 
Happens on positive and negative transitions
 
Very strange.