Baxi Solo PF 2 40 Loud buzzing/clicking?

Ok, apologies if there is a post already for this question. So, i have the above boiler & it has been working ok since we moved into this house. Recently it started making a loud buzzing noise which seems to come from the bottom of the cabinet. When making this noise, all the lights are out on the internal panel. At 1st the buzzing only lasted a few seconds, but now it goes on for ages, or until you turn off the electric supply to the boiler, or the timer kicks in & turns the boiler on. Even more recently, it has decided not to light, although the lights indicate otherwise (all alight!). When you go outside you can smell gas, so the fan seems ok & there is a gas supply to the boiler. Its got so annoying we have turned the heating off & have been using the immersion heater for water & other means for heating.

Has anyone had this problem before & had it sorted successfully, or does anyone know what the likely cause of this problem is?

Thanks in advance.