The other day, i let my younger brother sit in my car and he was playing around with the light switch. The offside bulb went out and everytime i started the car and put the dipped lights on. There was a buzzing noise from the offside lamp followed by the bulb not working message. 
 

i took out the headlamp, took the bulb out and put it back in and there were no issues for a couple days. Today ive started the car and the buzzing noise came back and the bulb has gone out again.

 

any idea what it could be?

There is probably a bad connection in the bolb holder or further back at the plug. Disconnect and clean all the contacts, including the earth connection of the bolb holder.

5 hours ago, cliffcoggin said:

There is probably a bad connection in the bolb holder or further back at the plug. Disconnect and clean all the contacts, including the earth connection of the bolb holder.

I’ve taken out the headlight (pain in the !Removed!) and there was a burning smell from inside the headlamp. I disconnected all the wires etc, plugged everything back in, put it back in the car and smoke started to come out of the headlamp. I assume the bulb is gone and I need a new bulb

Remember to press the contacts to ensure their springs are  operating freely.