As for me, it seems to be the time period since the last action in Dolphin which will switch off the bulb, even if the user is still online (busy with Ray Instant Messenger for example).
I'm using Dolphin 6.1.1 and that was already like that in 6.0.0003 I used before...
I'm using Dolphin 6.1.1 and that was already like that in 6.0.0003 I used before...