Record voiceover problem - blank clips laid down

Hello all, bit of a curious problem. I am using the FCP X record voiceover facility but after making a recording, the track laid down is mute / blank. It has no waveform at all, as if nothing has been laid down. This has happened with every attempt ,so I have reinstalled FCP X and tried again. Same each time since. The recording process appears to be working normally but nothing is in the track clip that has been laid down.

I have also used the Quicktime Player audio recording facility to test my computer. It all worked fine and I imported the quicktime audio to the storyline on FCP and played it back no problem. So what could be causing the issue here ?

I have also tried another USB mic system that was working fine on another computer with FCP X. That didn't work on my laptop either, same problem, goes through the motions, appears to make a recording and then you discover nothing is in the clip. I also tested my Shure kit on the other computer , it all worked fine, as you would expect.
I am using FCP X and a Coles Lip mic , a Shure X2U USB pre amp and a Shure mic to line amp to drive the mic before the Shure unit as on it's own it is quite hissy.

I have also deleted the FCP X preferences folders also and started again. I have checked all the clock speeds in Audio Midi and Sounds preferences i.e. 48k. I have tested the internal mic input also, it is the same , levels can be heard and seen but once the recording is closed and clip laid on the storyline , there is no waveform or audible audio within the clip.It appears that my problem isn't with my hardware as I know it works outside of FCPX on my laptop. It is a curious settings issue within my laptop. My kit plugs and plays on other FCP X systems. Audio can be imported no problem. It is just within the record VO facility. I have tested every setting within the VO record facility. Channel 1/2 , stereo, system setting ,internal mic , none of it appears to pass from the bus stage in the laptop.

Appears that the Shure X2U is driverless post 10.4.
Any help would be gratefully received ,
Cheers

MacBook Pro, OS X Yosemite (10.10.2)

MIDI/Audio set up won't have any impact here. First, quite FCPX. Then with the Shure X2U connected, go to System Preferences, to Audio, and be sure this mic is seen there, and set as the input. Also verify that you are seeing volume levels from the mic inside that window. And best sure you have phantom power turned on, definitely. Once that is working, only then should you launch FCPX, and open the Record Audio window (opt-cmd-.

On that specific unit, the X2U, be sure to turn the Gain on it up enough to get a good, strong signal. All the way down you'll not hear anything, from what I understand.

Are you seeing the interface listed in the FCPX audio record window for Input?
Are you seeing volume levels register in real time from the mic in that same window?

Use Control-Option-1 to make the Timeline show only waveforms, not any video, and set the Clip Height in the Timeline to maximum to be sure.

As far as I know, that interface should work fine with OS X 10.10.2, if you're on FCPX 10.1.4.

Thanks very much. I had looked at all of these options as well. What i have done differently is move my USB powered mic to its own usb port directly to the Mac. Previously I was using it as part of usb 3 hub. My Thunderbolt TS 2 station arrived today as I was having all these issues.So I set that up and changed the configuration. By doing that USB audio codec became an option on my sounds preferences , before it wasn't enabled. It didn't even appear at all. So I think the issue was related to congestion around a usb 3 lace hub I was using . 3 drives and USB preamp . Now that's out the way and drives are coming in via Thunderbolt, every mic option seems to work now.Internal and external.

Yep, USB hubs can screw with your mic input devices. Glad it's working!