Alarm Remote and Antenna's Argh....

Ok this one has got me pulling my hair out. After all these years. Have a Viper 791XV installed in wife's truck. Was working fine for 5 since early January. Now all of a sudden she came to me saying the remote wasn't working and that she had to set off the alarm to get in. I thought, well the battery was low so I'd replace it. Pop in a new battery, and it worked fine. Then a day later, she says the same thing is happening again. It just beeps at her with no signal. So I'd thought I check the grounds. Grounds seem okay. Alarm still functioning, dome lights, door triggers, and siren functional as well as door locks (ign controlled, not by remote) So pulled the battery cable off to look at everything. Ok. put it back on, and working again. Started the car, unlock/lock, and everything works. Walk inside the house, and come back out to show her, and it goes out again! Then after a while I got fed up and erased all the transmitters from the system using the learn routine. Ok. Then i went through again and programmed the default transmitter. Remote responds. Works fine for a few minutes and then back to the no signal. Antenna hasn't moved and it was working fine for 5 months or so before this happened. Since the shop I work for isn't doing DEI (no thanks to this crap) anymore, I'd hate to have to buy more parts. I would think it would be either the remote (which sucks because its the LCD, cost of 80.00, or an 2- Way Responder Antenna, (which no one will sell me). Is there anything I'm overlooking? I've tried 5 different batteries and each try has only brought 5 min or so of glory until it stops responding again. Any help is appreciated. It's a 1999 Ford Ranger w/ remote start, windows, and locks. All was working fine. I've checked the alternator, and it's okay. I'm at a loss of what to do. I'd hate to buy another remote or antenna to find out it doesn't fix it, and no other shop is willing to test it for me (why? this is the crap that DEI gives us?)

From what im getting from your post, looks like your alarm it self is fine, but i never work with the 2 way remotes. but still, sounds like a remote problem. maybe one on the buttons are stuck down, like to arm/disarm etc. mabey some thing doing it inside the remote. only thing a can think of. Kyle