My microwave maybe has any faults!! I always smelt something burning when using it, only first seconds. I examined and scrubbed it, but nothing leftover inside of this discount shopping microwave. Have you come across this problem? Do you know why? The brand of my microwave is Bosch, and the model number is HBC84K521B, Bosch HBC84K521B Compact Built-in Oven and Microwave. Do you know why? Please let me know! Thank you!