My MacBook Pro with Touch Bar (13-inch, 2017) makes strange cracking / static interference noise from the left side. No noise can be heard through headphones. First I thought it is the speaker, but it is is independent of the volume level and persists when headphones are plugged in. On the other hand, it appears only when the fans spin (as seen with iStatistica). I also note that the left fan spins always ~100prm slower than the right one.
At this point I suspect that it is a hardware problem based on the tests above, but I do not know if the sound stems from the fan or from the speaker but.
(I reset SMC and Pram, and run the apple diagnostic with found nothing.)
The computer is ~1.5 years old.
I am now wondering wether I should give it to repair, or if there is anything I could do myself. (E.g. if it is a software problem after all. I would also be comfortable opening the back to clean some airways or so, but do not plan to replace the fan myself.)