Hi, main problem here is that the air intake vents at the rear of the machine are blocked, this causes the magnetron to over heat in fine style and the machine usually shuts down in 29 seconds. Panasonic warranty their mags and inverters (PSU assembly) for 3 years. Contact me for advice
kindest regards
B.E.S. Microwaves
01424 447799
patrick
March 2009