Voice Command doesn't work / AT&T I777

[sbi]

My Voice Command doesn't work, either through a Bluetooth or directly with the SG2.
The Voice Command 'wakes up' when I turn the BT on. When I hit the DIAL button on my BT, nothing happens. If I press any of the Voice Command buttons it works fine (that is - "who would you like to call", or "Who would you like to text", etc.), and I can hear it loud and clear through the BT. However, when I speak to the BT nothing happens.
Furthermore, if I shut down the BT completely and want to use the Voice Command through the phone, I double-tap the HOME button, the VC comes up and asks me what do I want to do, but it still does not respond when I speak.

So it looks like something is wrong with the phone or with the Voice Command.

Any idea?

 

[KeiranSolaris]

I've noticed issues with the voice command if the screen on the phone is locked.
The headset seems to activate but then it doesn't do anything.
Unlocking my screen prior to hitting the button on the bluetooth seems to have fixed the issue.
Sometimes I've noticed that the first call I make gets all funky and I can't hear the other person through the headset when I use the button on the headset. If I use the app to initiate the call then it works every time. Headset is a Jawbone Era which I love and which works great on my previous phones.

 

[sbi]

I've noticed issues with the voice command if the screen on the phone is locked.
The headset seems to activate but then it doesn't do anything.
Unlocking my screen prior to hitting the button on the bluetooth seems to have fixed the issue.
Sometimes I've noticed that the first call I make gets all funky and I can't hear the other person through the headset when I use the button on the headset. If I use the app to initiate the call then it works every time. Headset is a Jawbone Era which I love and which works great on my previous phones.

Problem is that it doesn't even work without the BT. It 'talks' to me, but either doesn't hear my command or refuses to do it :'(