For Focusrite to turn round and say "Windows is not very good at handling audio" is really disingenuous!
 
I've been running their interfaces for the last decade without issue.
 
I know this doesn't help you but I am dumbstruck that they should make that sort of comment!
 
I bet it wasn't from their marketing team.......
 

Thanks for the replies.  My 2i2 is a 2nd gen.  It looks like the 1st gen  might be more stable.
 
 I do like the idea of setting up a separate user with different settings for audio use ( thanks paulf707).  I am currently working with Focusrite, but the fact that the 2i1 breaks up on two different machines with different chipsets and architecture makes me wonder if there is a hardware fault? 
 
I am most confused by the fact that increasing the buffer size doesn't help.  Even the UCA222 will play these projects if the buffer is set to max.  I retrieved my Tascam 1800 and tired it again, and it also runs fine with a  large buffer
 
If it can't be made to behave , I won't be completely out of pocket, as it is very good running a single VST instrument like addictive keys, so it will  become the interface to my laptop that i use as  a portable keyboard module.
 
In the event it can't be resolved,  any recommendations for a  budget 2 or 4 in/out interface?
 

The Tascam 2000 is the same unit as my us1641. There is no noticeable difference between my Scarlett 6i6 and the Tascam drivers and I'll also say pre amps. I actually find the Tascam Pre's are more forgiving when you have peaks in a live recording. I don't like the Focusrite pres much at all. My Tascam pres are certainly not noisy. 
So anyhow, you seemed to have traded apples for apples. And you issues are obviously to be found in your computer. 

Its interesting how people's perceptions of equipment vary I found the phantom power on the Tascam to be a bit noisy on certain mics.  There was a background sizzle that stopped if I turned of the phantom power  and let the mic run on the supply capacitors for a couple of seconds.  Probably faulty smoothing in my unit?  

Scarlett 2nd gen 6i6 and SONAR Platinum running on a stock Windows 10 HP PC with 8 GB RAM: absolutely rock solid since I bought the PC a year ago.
 
Hope I haven't just jinxed myself.

No problems with Focusrite (Saffire Pro40) here in the 2.5 years I've had it, using it with XP, Win8 and Win10. Your symptoms are probably not due to issues with the driver, but rather with some other software on your computer.
 
First check your DPC latency with LatencyMon. If it reveals excessive latency, then it's a driver (or potentially faulty hardware) that's interfering with audio streaming. If LatencyMon says all's well, then it's something other than a driver, such as a background process that's hogging the CPU or I/O bus.
 
Why on earth somebody from Focusrite would say Windows doesn't handle audio well, beats the heck outa me. It just ain't so. My guess is you heard from a new employee who was grasping at straws to close your support ticket. Focusrite support is usually much better than that.

+1 to checking LatencyMon. If you could run that and give us some insight on the offenders (each tab allows you to sort by column), that will give us better insight into your system. You only need to run for a few minutes while working, but can let it run longer if desired (but it does add latency on its own too).

Someone mentioned the beta drivers for Focusrite. They can be found here http://beta.focusrite.com. 

I just got a Focusrite 2i2. Been using a M-audio Fastrack for 10 years. Thought maybe a new 2i2 would be an upgrade. When I use a lot of my older Instruments like East West Instruments, I get very bad popping. When I hook up the old M-Audio they work fine. I'm using Sonar Professional that I had just purchased. I decided to reinstall Sonar 8.5 again 32-bit to see if there was any difference and the 2i2 works great. So it seems that the Focusrite doesn't like 64-bit. I got 1 reply from Focusrite when I contacted them which was no help. When I replied with more info that they said I would need, I was ignored. Guess I'm using my old m-audio and out the money.