Dom has pushed a fix see: https://github.com/raspberrypi/firmware/issues/195 I guess to https://github.com/raspberrypi/firmware/tree/master/boot (as the update time matches). I tried downloading the latest Raspbian image and then replacing with this firmware. But still no luck here. Anyone else had any luck? I'm getting good results using 16KB of nops, indicating 16KB direct mapped ICache. Cheers