Sync Issues ?

Here's my problem! Note * I'm having issues recording after selecting my from & to points, then placing Sonar in a loop so I can record every take.
 
Here's the scenario. Note * Regardless whether I am recording audio or midi I have the same issue crop up.
 
#1 - I will pre-select an area where I want my recording to start & stop, return to the start of the loop & continue recording until I am done.
 
#2 - During this recording process after about the 3rd. loop my midi data starts to go out of sync & gets worse as I go on. It gets so bad by the 6th or 7th time I have to stop & re-start the recording process as it is too far out to hear the down beat. This is especially noticeable on a snare drum but other instruments are also in this mess. It's kind of like drummer get's drunk un-reality show!
 
This has plagued my computers for a lot of years & I don't know what I can do to solve this? Since I've noticed this issue I have updated over 4 newly built computers & nothing has changed. I went from using a Mixtreme audio card to a Motu 828 Mk111, to a EGO SYS PCIe , to a Midas M32 & the issue still resides. This is like a tape worm that lives inside an animals intestine & continues to be found in the offspring.
 
My current setup has 4 SSD (solid state) drives & it still persists.
 
Can anyone help?
Cheers!
 

As Tom indicated, this has not been an issue for some time. When it was, the cause of most problems turned out to be having a non-zero gain setting in the synth audio track (sounds stange, I know, but true). If you're on an earlier version, you should check for this.
 
There are still cases where sync can drift by tiny amounts (like a sample or two) with each iteration that you would only notice as a phase error between a live synth and a bounced copy of the same track or a timing error over several dozen iterations of the loop. And I've only ever seen this happen when loop points are not snapped to measures or beats as they would usually be.