Thanks again for all the tips and suggestions.  I think I finally figured it out.  At first I didn't think that exporting the drum track worked....but in fact I think it will.  My original acoustic guitar tracks did not stay in sync when imported into Sonar...but that was because they were recorded while monitoring the drum track that I had recorded in real time to the HD24 while sync'd to SMPTE.  Even the drum track I had recorded to the HD24, when imported back to the PC drifted out of sync with the original Superior Drummer tracks.

If I export the drum tracks at 48K 24 bit (which is how I record to the HD24) and re-record my guitar tracks with that...I think everything will sync up fine.  Hardware synths do no drift at all and stay locked up tight.  The soft synths are what drifts when trying to record to the HD24 while syncing to SMPTE.  Strange but true, though I can't figure out why :) .

And yes...my way of doing things may sound convoluted to some...but it works for me.  I do 90% of my recording by myself.  And if I have my tracks on my HD24 I can sit in my isolated studio room and control everything in the control room by remote control.  I have two BRCs...one in the control room and one in the studio, but I can also just use the LRC since I have my studio wired for both.

Jesse...thanks for the tip, but this problem was the fact that everything started out sync'd during playback...but slowly drifted out of sync.

Bottom line is....I can't record soft synth tracks to the HD24 in real time while sync'd to SMPTE or they will be out of sync when played back either from the HD24 while sync'd to SMPTE, or if imported to the PC.  Hardware synths do not have to problem.

Thanks again...I learn something new about soft synths every day.

You  mentioned that problems occur once you start using plugins. eg Superior Drummer

SOANR does automatic Plugin Delay Compensation - there is a setting in Preferences where you can change what the value of that delay (measured in samples I think) is.

UPDATE:
Did some more testing on the timing problem.  I programmed a scratch drum track using my Alesis D4 drum module.  Then recorded that drum track to my HD24 recorder while sync'd to SMPTE via the BRC...(everything set at 48Khz 24 bit and SMPTE at 30 fps ND)

Recorded a couple of acoustic guitar parts while monitoring the D4 drum track off the HD24.

I transferred these tracks from the HD24 to Sonar on the PC.  I muted the D4 drum track and played the Superior Drummer track with the acoustic guitar tracks.  Everything plays back perfectly in sync using the internal clock in Sonar.

Now here's where it gets crazy.  While playing back the exact same tracks, I put Sonar in SMPTE sync mode...hit play on the BRC (HD24 tracks muted)...everything starts playing in Sonar again.  BUT....after about 45 seconds, the Superior Drummer track starts drifting out of sync.  Within 1:30 into the song it is REALLY out of sync to the point of a bad slap back sound.

So...soft synths play back in perfect time using the internal clock but drifts out of sync when sync'd to SMPTE....hence the original problem I was running into at the beginning of this thread.

I haven't tried mudgel's suggestion yet...but will do that the next chance I get.

OK... much has been said already on this. 

Keep it as simple as you can.

The more complicated the rig and signal path, the harder it is to work efficiently. 

Rip everything apart and start over.  

new system:  connect the interface to the DAW.  (pretty much done at this point)  
connect the mics and guitars to the interface for input
connect the studio monitoring to the interface outputs

use a mixer only if you need the preamps on mics or guitars..... hopefully the interface has nice pre's in it. 


Record and mix 100% in the box. 

I just described my rcording system..... except the mixer, because I do not have a mixing board. I operate 100% in the box with my system.  It hardly even looks like a recording studio except for the Yamaha DX27S and guitar amp on the stands.

Check out the music I make with this simple rig.

I am leaning toward doing everything in the box.  It's just that my whole system has worked perfectly in sync for years....until I started trying to use soft synths.  That is where the issue comes into place.  I can sync up the BRC with the HD24 and Sonar, and record tracks from my hardware synths to the HD24, all sync'd to SMPTE...then transfer the files to the PC and everything is in perfect sync with everything else in Sonar.

I agree with Jeff...   
Use the HD24 as A/D and a backup.
If your DAW is well configured, it'll be just as rock-solid... and you've eliminated a lot of busy work.
BTW, Look inside the HD24 (or other standalone HD recorder).  Looks an awful lot like a PC!  

Would this thread have anything to do with the issue?
http://forum.cakewalk.com/tm.aspx?m=2623609
 
Never had problems and still using an MQX-32M if you can believe it.

SToons...I saw that thread...I'm not sure if it was referring to my thread or not...actually don't think so, just coincidence I think.

I too still have an MQX-32M but haven't used it in many years.  I moved up to a Music Quest 8PortSE and used it every since, until I built my last DAW PC.  It doesn't have a parallel port so it doesn't work with newer motherboards.  I do have a WIN7 driver for it (written by a guy in Europe) but since I can't use it with my new build...I got a used MOTU MTP AV USB.

Both have always worked solid as a rock...until I started trying to use soft synths while sync'd to SMPTE.  I have my "problem" figured out...though not solved :) .

I actually had this happen the other night. My virtual PC had updated the flash player, then my internet audio wasn't working. I thought I might have gotten my mutes out of sync between the host and the VPC. Long story short, the 'System Sounds' in the volume mixer had become unmuted(ON). I did this when I was trouble shooting the VPC. This doesn't effect Asio mode, the same, but I was in WDM mode. Low and behold, I recorded midi/audio of the piano and audio from my Vocal mic at the same time and by 3/4 of the way through the song, all of the audio was a beat behind the midi. Really weird. Had to retrace my steps and found the System sound Unmuted. Mute it. tried again and that fixed it. Hope that helps. First time I'd ever had a track slowly get behind, like it was recorded at a slower tempo. Freaked me out. I was trying to finish a song demo on a time crunch.