Alarm triggering for no reason and unable to silence it.

[KyleNatolix5]

Recently I have noticed my E53 4.4i 2004 X5 alarm has been sounding for no reason. Its weird because the alarm will sound and I can not disable it with the FOB, but I can start the car and drive it while the alarm is still going off. I have checked fuses and terminals everything is good. I know it will be a huge amount to repair at the dealer. My cv joint axle just snapped today for the 2nd time in two months. That being said I am looking for the most cost effective way to go about fixing this. My thought was to purchase an aftermarket alarm system w/ remote start and have that installed. My question is, can I disable the factory alarm to stop it from interfering with the aftermarket one? Does this make sense coming from my angle? Delete the malfunctioning stock alarm system and replace with an aftermarket system?

EDIT: BTW HAPPY EASTER!!!!!!!!!