FM radio problem with Ford Focus 2007. HELP!

[TheMrIggs]

Recently I purchased a 2007 Ford Focus with 90k miles on it. When it was purchased, the antenna at the top was snapped off from a car wash or something so the radio was very faint and only like 1 channel worked. I finally got around to buying a new antenna to get better reception and clearer audio on FM and I purchased this radio base and this antenna. After recieving and installing them, I indeed got more channels and clearer audio...but every 5-10 seconds the audio goes faint and staticy. I figured it could probably be the factory stereo, so i replaced it with a double din kenwood stereo. To my demise, same problem. So I thought well maybe the antenna is faulty, so i ordered this "Stubby" antenna. It just came in today. I screwed it in annnd same problem. I literally have no idea where to go from here. Any suggestions?