Help! Imported audio out of sync

Okay so here are the vitals: Windows 7 UltimateX64, Echo Mia Midi audio interface, Sonar X1C Producer.
Here is the problem.  I just got the Echo Mia Midi audio interface. I take midi files and using soft synths create more realistic audio and then export each part separately into a mixing project.  I have done this for years and never had any sync problems with my old sound device. Since I started using the Mia Midi the tracks sound better but for some bizarre reason the exported audio tracks are out of sync by as much as 70 ms.  The files are all exported as WAV at 44.1/24 bit and imported to the same starting point, as I have always done.  The Mia midi latency is much lower than my previous sound device.
I am stumped.  I have rerecorded several times and the timing is different each time.  I haven't even gotten past bass and multi-tracked drums because it is so hideously off.  Correcting it manually on each track is out of the question because the project will end up with 22 tracks. I have messed with every setting I can think of that will effect the timing of an individual track during recording.
Has anyone ever experienced this?  Can anyone suggest a way to fix the timing issues in the actual recording process?  I am sure it has to do with the actual recording and not the importation into the project.  Please keep in mind the timing is perfect on the midi file and I have been doing projects like this for 6 or 7 years without issue.  It only started when I started using the Echo Mia Midi.  It sounds great but I am completely stumped about the sync issues.
Thank you in advance.

Well I updated to X1d but there is absolutely no difference. I have a usb camera but it is currently disabled. I only have the one sound card. Any other ideas?

Also make sure you have the most up to date drivers from Echo (and all of your devices for that matter). May not be an issue but it's always a good idea. Welcome to the forum.

I'm not sure I understand your workflow.  Why do you need to export the WAVs to a different mixing project at all?  Why not render them inside the current project (ie., bounce to tracks), save the project with a different name (project1-NOMIDI.cwp) and then remove the MIDI/Instrument tracks and then start mixing there?

Bit  rates will not be causing sync issues however sample rates will.

+1 to Herb (Guitarhacker) - not sure why you need to export those midi parts seperately

Well sadly the same thing happens. The problem is in the rendering process. And again sadly it is a Cakewalk issue because I tried it in Ableton Live 8 trial and it is syncing up perfectly. Urrrgghhh. I guess I'll be working in Ableton for a while.  I like it ok but Sonar is better for me. I wish Cakewalk support would get back to me. Oh well... at least it's not a complete loss. 
If anyone comes up with a solution please let me know.

I freeze the tracks to render the audio and then I export them. I just froze the synth tracks this last time and tried playing them back without exporting. The bass was way ahead of the drums. The problem is in the rendering. I tried to using the manual offset and that didn't help at all.