Small vibrations when charging Macbook Air 2020

I can feel small vibrations when I run my fingers in the area above the keyboard, below the screen only when charging. I've tried a few electrical outlets, extension cords and it isn't consistent. Sometimes the vibrations are there, sometimes they aren't. They aren't particularly painful, just alarming. I'm also worried it might reduce the lifespan of my battery? I do keep it charged most of the time because I've read in apple support that when charged to 100%, the mac bypasses the battery and gets power from the adapter which reduces power cycle and prolongs battery lifespan. I tried contacting Apple support, and they said it has something to do with my fan and asked me to reset SMC. That didn't help the issue. I just bought this macbook 7 days ago, never been dropped. Just worried my macbook might be broken and I need to have it replaced. Thanks for your help!