I did get a new cable.  Still a problem. 
I just replaced my tower with a refurbed Optiflex 7040. I have a Dell LCD TV W2300 (23" screen, speakers built in on the sides) that I've had for many years and love. I finally got everything hooked up and turned it on only to find that there is static coming from the speakers. It's not so loud that it distorts sound but if I'm doing something without audio, it's annoying. I had no problems with the Lenovo I had.  I tried several things. I removed and reseated the connectors. I removed the MaxAudioPro that came with the tower because I read that it's not a great app and causes issues. Still happening. Ran some diagnostics. No problem found. I took the green plug in out in order to reseat it only to discover that if I run my finger over the probe, I can make the sound flex in response to my movement! I'm not a techy and have exhausted everything I know how to do. If anyone has a suggestion I'd be grateful.  Thanks. 
Optiflex 7040, sound static, LCD TV W2300