Hello, please help, my interface is connected to the microphone and when i open Logic 9 it does´t work. But I opened garageband to check and it works fine. I can record voice with any effect... With Logic i see the sound passes in the interface.

Make sure you go into preferences in Logic and set the audio input to be your interface and the audio output to be either built in output or the interface, if that is hooked up to something else. It sounds like Garageband has the audio interface set as the input but not Logic.

Also make sure you close all other applications except Logic to ensure it is not running in slave mode...

Logic is NOT Garageband, it's not going to hold your hand, in Logic you have to learn how to set things up and configure the program.

You've already been given the answer but I suggest you start reading the manual, it will really help clear things up.

Make sure it's an audio track you are trying to record to and not a MIDI track as well.

Weird... the only other thing I can think of is to make sure that it's Record enabled with the red icon in the track. That's the only other thing I can think of but I'm assuming that's not it. Good luck with this!

Did you figure it out? The same thing happened to me. One day it was working and the next it wasn't without changing anything. I have the channel strip record enabled and the interface set in the audio preferences and still on sound goes into Logic with either a mic or guitar.... Any solutions out there?

you have Logic's Preferences Set Correctly

http://help.apple.com/logicpro/mac/10/#lgcpbb81aca5

Are you recording on an Audio Track not an Instrument or External MIDI Track

Do you have the correct input selected on the channel strip?