I recently paid 60 euros to get my 14" m1 macbook cleaned, it was extremely dusty inside, so much so that the left fan started making strange squealing noises and then a pinging sonar-type sound every few seconds. Luckily with the combination of the fan control app and the built in apple diagnostic tool I managed to determine it was probably the fan and brought it to the local service shop to disassemble and clean. Now the only things left are to replace the original battery which is at 75% and replace the rustling speaker which was damaged by ants getting inside through the vents and chewing on it.