Baxi system boiler cutting out

[torqueofthedevil]

Noticed the water has not been as hot over the last week. Put it down to weather but now it's freezing. Water was set to constant but boiler lights for "pilot light" and "burner" were off. Turned it off and on. No changed. Left it off 5 mins then turned on. Fires up but after a min sounded rough and cut out. Auto re ignited but same again. Did this twice and then stayed off. Any ideas?!?!? Not looking forward to a cold shower tomorrow morning!

Cheers