I have an issue with my 8100. It is running the 4.5.0.42 build of the BB OS. My ‘mute’ key, under the previous OS versions (4.2), turned off the screen and locked the keypad entirely. Once the mute key had been pressed, the only way to get the screen back was to press the mute key again. This was quite beneficial for my battery, as the screen would not be turned on every time a button was pressed.
I am posting, because I want this behavior back. Currently, the device will go into standby mode, but any time a key is pressed, the screen comes on and reminds me to press the mute key to exit standby. This really defeats the purpose…
How can I get my mute button to be a real standby button again? Is there an application or a setting I don’t know about? Can this even be fixed on the 4.5.0.42 os ?
Ok, I upgraded to 4.5.0.42 and the problem has *mostly* gone away.
When in ‘stand by’ the phone will not respond to any key press _except_ the call, menu, back, or end key. These keys are just as likely to get pressed when in my pocket, as the de activated ones, so ‘standby’ really isn’t all that useful.
How can I make standby a real standby, where *no* key, other than the mute key, can bring the device out of slumber?
The standby key is still useful. The top rows of keys only light the screen for about 2-3 seconds, enough to say the device is in standby and pressing the trackball does nothing. Even when one of the "still active" keys is pressed, nothing happens except for the momentary notice that the device is in standby. I use standby when it's in my pocket and it still works very well. It's better than key lock because it can't accidentally do an emergency call like it can in keylock.
my screen lights for 5 seconds then goes out. i guess those extra 5 seconds times 20 or so random pushes a day aren't going to take that much from the battery.
Mute / Standby key not (really) working ? 
