I've heard of this issue once before on a forum, though I can't find a web link for it. This is a long shot, but you might want to try this Windows setting change for negating a humming mic (the camera has a built-in one).
On my PC, I have the camera in front of the monitor, with the PC right next to the monitor. When the camera is active, there is a noise similar to what you are describing because the camera's sensitive mic is picking up the nearby noise of the PC's fan blade.
Sorry. I meant as in the device itself it making a sound. It's not from recording and playback my speakers. Now that I research some more, there's no speakers on the device just a microphone. I'll search some more as well.
I'll also contact tech support. Thanks dude.
You're very welcome. I have heard of a hum being generated by electronics because of a faulty capacitor component, but it's much more likely to be related to the mic. Assuming it is always receiving a little power when plugged into the USB even when not in use, one would think that it would hum all the time if it was the capacitor, not just when its green light activates when running a camera program.
All the front cameras (various F200s and SR300s) I've used have done the high pitch squeaking thing when active. I've never done anything with the microphone so I assumed it was something to do with the laser projector.
The RealSense camera also acts as an ordinary webcam for applications such as video chat and live video streaming / recording. The PC will also use the RealSense mic as its default general mic. I just confirmed this by switching on recording on my audio editing software, and the mic picked up and recorded an advert on the nearby television. This was with the RealSense camera in its inactive non-green light state.
If all of your cameras squeak, this reduces the likelihood of it being a hardware malfunction. Having said that, if it was just simple mic noise then one would think that the noise would also be apparent when using non-Realsense applications that have sound.
I tried broadening the research on the problem by googling for 'webcam squeaking' and found a number of posts about people experiencing this with ordinary webcams. People knowledgable in the subject thought that it was caused by signal feedback. One suggested cause of this was speakers being placed close to the mic and generating signals that were being picked up by the mic.
If you do not have speakers near the mic, do you have other signal transmitting devices placed nearby, such as a mobile phone or wireless land phone? I remember reading last December about how people's wi-fi could be affected by the electrical signals from the lights on their Christmas tree!