clear reception then no signal

[Hiker Dude]

Here is my antenna location report;

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d46ae9cd917541d
For about the past year now I have noticed that WTAJ (real channel 32) sometime after 6:00 PM EST starts to freeze then no signal then back to normal.
As the evening goes on, this gets worse. During the daylight hours it is crystal clear with no issues. ( unless there is bad weather) All the other channels in that area where the antenna is pointed have no issues. 24, 46, 22,34, and 8.
I get a lot more channels very clear as well without rotating with a total of 13 stations
My antenna is outside about 28 feet AGL.
I have a rotor that I use to rotate the antenna ever so slightly to pick up the WPSX stations. These stations seem to elude my antenna unless I rotate it ever so slightly a couple of degrees.
My antenna is a channel Master CM3020.
I have a Winegard HDP269 12 DB preamp installed at the mast with about 10 feet of RG6 cable between the antenna and the amp.
From the PreAmp to my ground tap ( just before it enters the house), is 50 feet of RG6. Then from the ground tap to the power injector inside my home is about 8 feet.
from the house side of the power injector I go to a 6 tap splitter for 6 televisions ---model --Extreme BDS106Vf (5-1,000 hz ).
I removed the splitter out of the picture for trouble shooting purposes and tried two different televisions separately hooked right to the power injector with no improvement.
Any suggestions on what I can do to eliminate the channel 32 ( WTAJ) issue?
I am even open to a new antenna or a new preamp if it will help!!
I could go about 4 feet higher, but in order to do that, I would have to lengthen the coax and the Rotor cables, so I am trying to avoid that.
Everything is crystal clear except WTAJ !!
Beautiful HD clear until night time or if there is a storm, then clear, freeze, no signal and repeats.

[GroundUrMast]

Have you tried lowering the antenna? 4" to 6" increments have been known to help locate a 'sweet spot'.

I'd try the extra 4' of height as well. One month's cable bill will buy you a connector installation tool kit and the cable at a big box home center.

I'd experiment with the existing antenna before replacing it or the preamp.

[Hiker Dude]

I will try raising the antenna first.
I can probably go about 4 feet and replace the existing coax.
I have the tools for cutting/prep/and crimping along with good barrel outdoor type connectors.
But i will need to solder splice and put water tight shrink on the rotor cable to get enough length. I believe splicing it shouldn't be an issue.

[ADTech]

Try lowering it first in 4" increments". Doesn't require any special tools or extensions to the rotor cable.

[Hiker Dude]

I will give that a try next week .
I will try lowering it in small incraments.
Right now I am just about 12 feet shy of clearing the trees that are about 50 yards away. I was concerned that lowering might make more issues. But the suggestion for lowering is easier than raising and worth a try.

[teleview]

Use this for outside splicing , and water proof other connections. http://www.coaxseal.com