Pioneer 03: automatically switches source after power on(what's the cause)?

[zodiak]

I have a pioneer elite 03 that's just over 1 year old and noticed
something disturbing recently, when I power on the pio 03
it will power up to hdmi(where it was powered down from)
roughly 5-10 seconds later it will switch to fm automatically

now I'm concerned as to what's causing this to occur,I notice as well
when turning off the unit the blue power indicator light
will take awhile to turn off

I have a 1 year old even though we have child gates around the
equipment he can occasionaly reach through and push buttons

has some setting been changed or this an indication of a real problam?

Thanks