Currently experiencing an issue (incredibly intermittent) with the alarm and the locking system.

The way I expect it to work, is that when I press once on my key fob, the car locks, then when I press again, it 'dead-locks' and there is an audible beep, confirming that it's locked properly.

However, on occassion, the car's now taken to
1) Not always beeping when dead-locked
2) Not always unlocking the passenger doors when I press the 'unlock' button, but still unlocking the driver's door
3) Not always locking ANY of the doors, when I press to lock
4) The alarm going off for seemingly no reason when locked
5) Sometimes it will single lock, but will not dead-lock
6) Sometimes not unlocking ANY of the doors

I'm really not sure what it could be, it went to Jaguar some time ago because I was having issues with the alarm going off in the middle of the night for several months, and they were of no help.

I've replaced the battery on the key fob, but I'm not too familiar with the locking system.

I really should add though, it's very intermittent. Sometimes, the car is perfectly fine, other's (like this afternoon) I'm left stood out on the driveway for 20 minutes with the alarm going off, trying to figure out what's going on! The last time this happened was 2 weeks ago, but it hadn't happened for several months before that.

Just another note as well, I'm aware there's a little section in the menus that you can supposedly see what set the alarm off last time, but every time I look there, it's greyed out, as though it's unavailable. Any ideas?

Any help would be greatly appreciated.