Hi. I've had my vrs TDI EST for just a year now and lately the alarm goes off unannounced usually just when i get to sleep! So I'm having to double click the fob so as it's locked but with no alarm. Anyone any ideas where I start finding the fault??

Welcome.

I do not know Octavia Mk2's, but

It may be as simple as the battery going flat in the Alarm / Siren.   They are a consumable eventually.  Some fit another battery,most get a new alarm / battery unit.

Ah! Didn't know the alarm siren had a separate battery. I'll give that a look. Thanks

Hi,  Your horn problem could be as simple as  a moth or butterfly wakes up when it is dark, that has got into your car sometime during the day. I had exactly the same problem last Summer and it turned out to be a moth which had come into the car and was on the driver's door. The horn would go off when darkness descended, and it took three nights to discover the moth. Terry

You can test the above by turning off the internal sensor by using the switch at the bottom of the door pillar on the driver's side.

See handbook for details.