Just got a 2i4 2nd Gen so I could record guitar DI in the apartment with Bias FX. In stand alone applications it works as advertized, BUT-
 
Issues in Sonar.
Setting the ASIO buffer size at 64 with sampling rate of 48khz works great but the Total Roundup (input and output combined) of latency is 7.8 msec. If I set the ASIO to 32 at 44.1 the total roundup in latency is 4.2 msec which is great except the audio has major issues with glitches, pops, and severely suffering quality and the CPU meters in Sonar peak. The CPU meters will almost peak with a single track of BIAS at these latency settings, so it's not track count or plug-in use. 
 
I've tried everything in this thread with the exception of that program someone mentioned that seeks out sources of latency issues. 
 
Next place I'm looking is for tutorials on deeper Settings in Sonar, maybe I'm missing something. Then I'm going to try this out in Pro Tools (don't kill me).
 
For specs I have a custom built PC, a little old but still decent:
 
Processor: AMD Phenom II X4 965 3.4 GHz
RAM:         16 GB
OS:           Windows 10 64-Bit
DISKS:     C: SSD for OS
                D: SSD for audio programs
                E: SSD for sample libraries (East West)
                F: HDD for mass storage
I have a USB 3.0 PCIe card, but I haven't been able to remedy this on that card or any of the USB 2 ports.
 
Also, in the midst of all this I had gotten a watchdog fault that resulted in my doing a clean install of Windows 10. Which is why I now have all my audio programs on a separate disk. 
 
Any suggestions would be very appreciated. 
 
Thanks
 

You wouldn't think so. I've played with higher settings in other situations but in the this case it's a noticeable difference. Selecting Input Echo is the only option I know that will let me hear back the armed track but I get about an 8th in delay. 
 
 
EDIT:
It was the automatic plugin delay compensation. I switched it off and it took care of the issue. Some of the other tracks had delay as a result but turning input echo on for all of them during recording fixed it.
 
Haven't used Sonar for recording live audio in ages (was renting a studio that used PT LE which had no PDC), total newb mistake.  

Thanks for the advice on that bit. I probably have that on a gate or two.