我的EM5开机后就有呼呼呼的声音，就好像旧电脑风扇的噪音一样，当然咯没有那么响，我又试了下我的EPL1，开机后很安静啊，要贴近耳朵才能听见细微的声音。
不知道是否正常？

以前就讨论过了，新五轴防抖的问题，甚至你关掉防抖也一样响，原因是它一直就靠这个固定，除非掉电复位。

自己搜到了一些相关文章

转自43rumors:
Sound Noise
In these days our readers will hopefully receive their E-M5. But the first thing you will notice once you unpack the camera is the Sound Noise you hear when you turn on the camera. It’s pretty annoying but on the good side you here it in a silent ambient only and it gets away during video recording. Olympus issued that official response to explain the Sound Noise you hear on the E-M5: “You are hearing the new 5 axis Image Stabilization system. It uses a type of Magnetic field to keep the sensor assembly suspended so you will even hear it if the IS system is disabled.”
My very basic question is. How is it possible that you don’t hear the noise while recording movies? I mean it’s not that it stops working …so would it not be possible to turn the noise off while shooting photos? Hmmmm.

5轴防抖产生的噪音貌似？