Hi-
I’ve just tried 3 microphones on my macmini and nothing seems to work. Is my mac broken, or do I need a special type of mic? The settings seem to be fine (I’ve tried many variations), and when I plug-in and unplug a mic, the meter jumps and the speakers click. But no noise comes out afterwards.
-Tcat
micmacpaddywakgivvadogabone
(had to be said)
This is a USB microphone you’re using, right?
No.
I just read the manual…grrr…the input audio port is not powered.
So, I guess that means a USB mic should work?
But I don’t have another USB port left! Sigh, I guess I need that nifty external HDD and hub…And a new USB mic…
Damn damn damn. I should have dropped the extra bank on a powerbook.
-Tcat
Why would noise come out of a microphone when you plug it in? Noise comes out of speakers, not microphones!
I’m probably misconstruing what you’re saying. You probably mean you apparently aren’t getting any signal when you try to record, yes?
Go to Apple Menu, System Preferences, and pick the Sound prefspane. You may have multiple choices for input options. You want “line in” to be selected, if the microphone has a standard stereo sound jack; if it is indeed a USB microphone and you’re plugging it in to the USB port, it may appear as “USB microphone” or some such thing instead. The “line in” port may be the default. (My computer is a PowerBook, which has a built-in microphone which your Mini does not have, and on mine the built-in mike is the default, so I’m not positive that “line in” will be your default).
You’ll also see a slider that lets you adjust Input level. Obviously it has to be not cranked over to the far left which effectively sets the input level to 0.
EDIT: never mind, I see you’ve got it figured out.
I have seen USB microphones working on a Mac mini, so the answer would be yes in your case, I hope. Unfortunately you will need a USB “hub” or whatever it’s called.
I am sitting in front of my Mac Mini, typing this. Yes, we get one USB jack but the hub I bought for all of $ 39.00 ( MUCH less than the difference between a Mini and Powerbook ) works just great. I’ve got a Skype headset jacked in, a USB flash drive and my Tréo cradle. I can use more than one at once, the hub handles the flow just fine and dandy.
Make sure you go to System Preferences and adjust the mic and speaker input and output choices, and volumes, after you plug the new device in. That way, you can record what you want to ( or, talk to people with it ) and hear what you want to.
Additional unsolicited info: If you are using it for Skype, you ALSO must go into the Skype preferences to adjust input and output on audio, otherwise the Skype software may seek native speakers or mic jacks instead of the USB items you wish to make use of.
Cartooniverse, who lurves his Skype to pieces. 
If the port is unpowered you need a ‘dynamic’ microphone or a self-powered ‘condenser’ microphone instead of an unpowered ‘condenser’ microphone. One way to make a self-powered condenser microphone is to plug it into a microphone pre-amp and then into your unpowered port.