So... I have no idea whether this is an issue with my iPod or a known issue with iOS4, but fingers crossed I'm not the only one with this issue -- When I'm playing music in my iPod through my speaker dock, with the iPod locked to save battery life, the machine automatically switches itself back on (to the 'Unlock' screen) at the beginning of what seems to be every third or fourth song, seemingly for no apparent reason. It doesn't interrupt playback and doesn't have any detrimental effect whatsoever, it's just exceptionally annoying (and potentially battery draining?). There's nothing touching the screen, nothing that might be inadvertently hitting the Home button, it's docked perfectly snug to the speaker (no chance of it wobbling or accidentally undocking itself), and there's nothing special about my speaker either (literally, it's just a standard speaker with a built-in iPod dock); so far as I can tell, it doesn't do this when the iPod is sleeping, just when it's actually playing music. Any similar experiences / advice / explanations?