So U have tested and it seems like the Tascam (with the new driver) doesn't like ASIO but does like the WDM driver setting. A couple of questions, 1) For the distance between samples (for the manual offset) does it depend on the tempo? 2) If I use the manual offset will it affect the wave files, for example if I wanted to send my waves to another studio to mix? Or if I want to send the waves to my drummer to mess with who uses Ableton?

The new driver  ( for the us1641) was a total disappointment. No change at all for me. Still reporting a RT latency of 50ms. Lower than that I'll  get crackles.  
 
So I changed to WDM mode and ran the test and then set the buffer slider in the middle somewhere. The crackles are gone and everything seems to work fine.  
But I lost the outputs 3/4 ?? so I switched back to ASIO. 
Anyhow, we are still dealing with crappy drivers. 
The same computer has no issues at all with my Scarlett. 
 
I'll run the loop back test later. 

Very interesting results, but no surprises. Basically the Tascam in any mode at any settings sucks. 
So here's some screen shots of my test. 
First I'll show this screen shot of after I ran all 3 modes. 
Top track 6 is original Midi drum track. 
Next 7 is the frozen Session drummer audio track. Note- it lines up to the sample with the midi event. 
Next 8 is the Tascam ASIO mode at Normal latency - it plays ahead by about 300 samples. ?? 
Next 9 is the same but at the highest latency setting - It is exactly the same so buffers are not involved with this issue. 
Next 10 is in Tascam WDM mode... it's late by 800 samples. 

This is Tascam ASIO normal setting 

 

 

Here is my Scarlett 6i6 in ASIO mode. I tried to test WDM but it said this was not possible. 
Anyhow I tried a bunch of settings and all gave the same results. Bang on the money. 
 

 

http://www.cactusmusic.ca/images/Scarlett%20Sync.png
 
So as you see drivers do make a difference and sloppy timing is just not exceptable  to me. 
 

Johnny, I don't quite see what you're doing here so I have some questions that may or not make sense.
 
How does an interface come into the picture when you're playing a midi track ?  Are you doing a loop back or something ?
 
How can an interface react to a midi note before the note happens ?
 
The tracks using the Scarlett look more like noise than drums.  Is there supposed to be a hit like with the Tascam ?
 
 

Good question. 
Like I said I froze the session drummer track which creates an audio track. 
That track lines up perfectly with the MIDI event.
 
I really doesn't matter, mid or audio,  the point is that what your hearing at your audio interface is not in time with what your recording. It's out by enough to add up to a sloppy recording. I think the issue is people are unaware that this might be happening to them. As I mostly use the Tascam for live recording, it matters not. But overdubs would not be perfect. 
 
 Sorry the Scarlett screen shot is the wrong one I just noticed.. I had a better one. and I'd have to go fire up my DAW to get the right shot. I'll edit it later.. But trust me, everything was lined up to the sample. To me that tells me I'm using the right interface. 

Thanks guys for your help. Hey BobF the 2119 was way off so I guess I do something wrong in my measurements. After some fiddling I have found that around 804 seems to work, though I recorded some tracks last night that may seem to differ, but could have easily been sloppy playing. Any thing else I should be looking at?

Also i asked before but not sure anyone could answer but using offset, when I export tracks for someone to use in their DAW will this creates timing issues like with click tracks and the like?

On my 2.2 Ghz i7 16gb laptop using my Tascam us1641 with the new driver ("new"? Hmmm)at 44.1, shows 18msec 793 samples and at 48kHz is showing 16msec and 793 samples. I don't see any difference from the previous driver. I haven't tracked anything with the new driver yet, but plan to today. If I have enough time, I will try it also, on my new i7 4790k desktop. 
Man, after getting happy about there being a new driver, I feel sucker punched by Tascam. After years of great gear, I feel "untrusting" of them, now. So, it seems, I will still be looking for a new I/O.........
Michael
 

Sorry I haven't had a chance to test if mine will swicth to 48 Michael. Once I finished the Jazz recording I had to swicth back to my Scarlett to continue with other projects. I didn't want to have Sonar freak out about the interface. It actually doesn't freak out much because both have the exact same output configuration. 1/2 - 3/4 and SPDIF. 
Might try it tonight. 
But as I said there was a huge differance in the performance when using the better computer. The RTL will not change much because that's also partly a hardware issue and those hidden buffers. So you won't get better latency no matter what. But the fact that the driver seemed more stable than before and also the reported latency was very close this time make me think they did improve it somewhat. 
 
While I had it hooked up I fired up a project with a lot of tracks and both VST's and effects. 
This was where the Tascam bombed out on me in the past. It couldn't handle big projects. I bought the Scarlett and the problems went away immediately. But now the us1641 is working just fine. So the computer must be a factor. Make double sure the new drive did install properly. 
Tascams driver install is terrible and I think this is part of the problem. Example. on the first office computer I originally did the loop back test  ( bad results), Windows 8.1 had always flagging the Tascam as not installed properly in that fix issue task bar thingy. That computer had the original 2.1? driver installed first and then I updated it to the new one. 
On the DAW where it's working properly  I never had the old driver installed, I don't have that message. 
If I have time I'll try obliterating all traces of the Tascam's drivers and re installing the new driver and see if it works better. It might be one of those issues for you too.