The other day I decided to play the Resistance demo, but after the PS3 logo appeared on the screen it just went black. I don't know if it was frozen or just slow, but it didn't seem to load after a minute or so, so I did the force shut down (hold down power button for 10 seconds) and turned it on again and then Resistance ran fine.
Later on, I was watching the LittleBigPlanet trailer from the US PSN (is it just me, or is the audio out of sync?) and I went straight into the Motorstorm demo and same thing, PS3 logo appears and then nothing. Turned off and on again, and it was fine...
Should I be worried, or is this normal?