I have weird sounds problem with my Chromebook whenever I charge it.

I have weird sounds problem with my Chromebook whenever I charge it. and it comes from the left side of the laptop. I also went to the shop where I bought it a year ago. they found no problem with it. but it only happens when am home. they fix it. sound on the laptop go loud when I come back from the shop. but it go low when i used my charge.

Should i go back to place and get new laptop or new charge for same laptop i have for an year now.