Sounds like when a cable is bad (but not my case), i'm hearing from time to time a long static interference when recording and sometimes when listening back. Have my buffer set at 512. 

Have you used resplendant's latency monitor to check your machine?
 
It makes sense to rule that out first.
 
http://www.resplendence.com/latencymon
 

Thanks. I did just download the monitor and all was well.
 

Next, are you live recording when it happens or does it happen when mixing.
 
I'm wondering if we can exclude external hardware.

I agree with the above. Rule out external hardware, other USB devices, mobile phones etc. It sounds like you are suffering from interference, but there is not really enough information to go on..

I  use to get what sounded like a electric snake slithering through the cables... then I started using a power conditioner...

Electric snake heh.... That's a great name for a band......

is your internet connection a wireless set up ?
Turn it off in device manager and re-test.

It happens both ways. I could record a section, the shorted out wire hissing sound happens, and it wouldn't even be recorded. Just annoying. Some pops have recorded at times. Also same with listening back. My internet connection is ethernet. It has wireless capability. Maybe I should still turn it off in device manager, (or is that taken care of when I'm hard wired?)

it depends if you have a wireless connection on that PC, even though you are hard wired, it wont matter, it will still cause interference. if you go in to device manager under connections you will see it if there is a wireless connection.
This has happened to me before and it does sound like a classic case of interference.
If its a grounding issue then try plugging all your gear in to 1 outlet. this will avoid using 2 power sources on different breakers which is always a problem with grounding.
 
However it could be buffer rate is low, possibly a bad USB cable or even a bad USB port.
 
Ill share a story with you,
2 years ago I had this god awful crackling going on and it miffed me beyond belief.
It turned out that I had been connecting and disconnecting my Audio interface/soundcard to the front USB hub in my PC front panel. After doing this 90000 times, I wore the USB port out.
So it was making a connection but not a total connection. So I reinstalled the drivers and used the second port (right next to it) and never had another problem.
 
However now I use a power conditioner to shut all my audio gear down at once. (1 switch turns on speakers and soundcard). So a cautionary tale about wearing out USB ports. it happens.
 
It can be frustrating no doubt figuring these things out but here it is...
Break it down to simplicity, start ruling things out 1 by 1. cords, wireless, ports, power adapters for gear. sooner later you will find it. lets just hope it is sooner than later