Wesley wrote:
Breville Lightening two slot electronic toaster, such as

http://uk.shopping.com/Breville-Lightning-PT15/info

Loud humming starts as soon as I put bread in and depress the lever and
stops when toast is done. Toast is still done properly. I've tried
pressing on the side of the casing and in certain places this deadens the
sound somewhat. Tried Googling but can't find any explanation.


It is almost certainly crumbs in the solenoid that holds the pop up
mechanism in the down position.
Open it up and clean it out.