I don't have a Focusrite, however I was having popping and clicks when recording.  At the time I had installed Google Chrome browser and it installed an updater program.  The updater program was causing the "interrupts".  After uninstalling Chrome and the updater program the problem went away.   I had another problem with clicks and going "off line" (disabling the Ethernet controller) cured those problems.
 
I do some support on computer forums and pops and clicks is an often reported problem in PC audio.  There is no "one fix" however Wi-Fi is one known cause and disabling it fixes those cases.  Others can be audio and video drivers.

Another question - are you plugging in to a USB2 port or USB3 port.  If you are using a USB3 port, try a USB2 port.  Also, are you using ASIO drivers or something else?
 
Also, what plug-ins are you using?

Good point on USB 2.0 port.  I forgot.  I had an issue with my new MOTU 896mk3 Hybrid.  I was getting intermittent pops and it turned out that I had been using (several) USB 3.0 ports.  Moved it to a USB 2.0 port and the pops went away.

dwardzala
Another question - are you plugging in to a USB2 port or USB3 port.  If you are using a USB3 port, try a USB2 port.  Also, are you using ASIO drivers or something else?
 
Also, what plug-ins are you using?

I do not have any usb 3.0 ports, all 2.0. I am using a ASIO Driver. I also had found that when I set the buffer size to 128 I get no playback whatsoever. Low latency was one of the main selling points for me, yet it has been the exact opposite.

I have first generation and have NO issues.

Be aware there are TWO separate drivers on the Focusrite site.
ONE - is for USB 3.0 Ports
ONE - is AMD specific CPU's WITHOUT USB 3.0 ports and is only
seen under MORE DETAILS
 
AMD SYSTEM USERS
If you're using an AMD system you should connect your Scarlett Interface to a USB 3.0 port after downloading and installing the driver. 
If you don't have any USB 3.0 ports available on your AMD system, please download and install this driver instead before connecting your Scarlett Interface to a USB 2.0 port.

Buss power, I myself think buss power is a bad idea. 
 
The Tascam US 2x2 comes with a DC port so you can use either USB or DC. 
 

cclarry
I have first generation and have NO issues.

Be aware there are TWO separate drivers on the Focusrite site.
ONE - is for USB 3.0 Ports
ONE - is AMD specific CPU's WITOUT USB 3.0 ports and is only
seen under MORE DETAILS
 
AMD SYSTEM USERS
If you're using an AMD system you should connect your Scarlett Solo to a USB 3.0 port after downloading and installing the driver. 
If you don't have any USB 3.0 ports available on your AMD system, please download and install this driver instead before connecting your Scarlett Solo to a USB 2.0 port.

Sorry Larry, I'm just not seeing this. I've checked the downloads links for both 1st and 2nd generation 2i4.
 
Under more details I only see USB 2.0 driver: 2.5.1. However on the 2nd generation download site, they link to a 1st generation driver (as an advisory) which takes me to a 2.5.2 driver download. There must be a recent update.
 
However, I do not see the driver download for AMD CPUs with USB 2.0 which is what I'm going to setup, hopefully next weekend. Can you please point me to that.
 
Or is that what you see when logged in with a registered product?
 
Keep in mind, I am still unable to register my 2i4 (haven't heard back from support on my trouble ticket)
 
Thanks kindly :)

robbyk

cclarry
I have first generation and have NO issues.

Be aware there are TWO separate drivers on the Focusrite site.
ONE - is for USB 3.0 Ports
ONE - is AMD specific CPU's WITOUT USB 3.0 ports and is only
seen under MORE DETAILS
 
AMD SYSTEM USERS
If you're using an AMD system you should connect your Scarlett Solo to a USB 3.0 port after downloading and installing the driver. 
If you don't have any USB 3.0 ports available on your AMD system, please download and install this driver instead before connecting your Scarlett Solo to a USB 2.0 port.

Sorry Larry, I'm just not seeing this. I've checked the downloads links for both 1st and 2nd generation 2i4.
 
Under more details I only see USB 2.0 driver: 2.5.1. However on the 2nd generation download site, they link to a 1st generation driver (as an advisory) which takes me to a 2.5.2 driver download. There must be a recent update.
 
However, I do not see the driver download for AMD CPUs with USB 2.0 which is what I'm going to setup, hopefully next weekend. Can you please point me to that.
 
Or is that what you see when logged in with a registered product?
 
Keep in mind, I am still unable to register my 2i4 (haven't heard back from support on my trouble ticket)
 
Thanks kindly :)

Just use the link in my post...it's a direct download of the driver....

You have to click "Details" on the Focusrite site to get to the driver...

All right, Focusrite tech support gave me a new bundle code for my missing (open box or dented) store bought version. So wonderful of them, so now I am off to the races.
 
I am going to set up a separate recording station in my house in a large area which will be wonderful for live singer/songwriter takes, demos, etc. I'll be using my old lexicon reverb hardware unit.
 
I can then take the tracks into my main studio (aka boxed in bedroom) for any final eq, limiting, etc...
 
I used to do that when I 1st started learning DAWs in 2007. In 2009 I was using Ableton and making some nice demos in this same way. However, my Yamaha speakers were on loan and they were called back. I bought my new rig and my Sweetwater engineer recommended Sonar, I moved all the way into the box and that's the rest of the story.
 
Almost 10 years now (with 2009-13 missing in action) and I think I'm getting a bit of a grasp on this whole thing. I dug out my 1st song ever recorded in 2007 and man, there was a lot of room for improvement :)

Hey Larry where did you get that driver in the first place? I have the 2.5.1 Driver and the 3.2.2 Driver from the beta site. Just wondering when it's dated for/how old it is. Thanks