Car Alarms: Problem with Viper 700 alarm, valet mode, viper 700

Question
My Viper 700 alarm will sometimes start constantly locking, then unlocking the car while it is sitting idle. The lock behaviour is just the normal passive lock sequence. But why on earth does it then immediately (typically 1 to 10 seconds later, a bit random) UNLOCK it?

The unlock also happens when I manually lock it. Wasn't doing it yesterday, but is today, and I think it's had this behaviour on *occasion* since I got the car (with the alarm pre-fitted).

For now, it's in valet mode and all is fine if I'm prepared to leave it unlocked. But apart from waiting for it to fix itself this time around, or run the battery flat, any suggestions for a longer-term fix?

Thanks!

Answer
I would strongly recommend taking a look at the ground connection for the system.  The ground is a black wire that should be run to a ring terminal screwed to a piece of metal that has had all paint/primer removed.  It should be run to a part of the body that is not bolted, like into the kick panel.  

Random behavior like you are describing is almost always attributed to a bad ground connection.