I’m trying to craft up a little podcasting rig here in the office, something better than using the built-in microphone on my iMac. I’ve had a Griffin iMic hanging around, and I bought a Omnidirectional Tie Clip Microphone from Radio Shack this afternoon.
I tried a different Mac, and a different microphone, but the hum remained. Then I stumbled across the helpful Fixing white noise and 60Hz hum when using an iMic and Final Vinyl, which advises, in part:
- Flip the switch towards speaker. This will amplify the signal coming in.
- Go to Applications-→Utilites and run Audio MIDI Setup. Set the “Properties For:” to iMic USB Audio System and make sure that both input and output are set to 16bit 44100Hz 2 channels. Most likely it is set to 8bit.
I have no idea what this actually does, but it worked, as you can hear clearly if you listen to the attached MP3 file.