Hey Lotsa!
There has been some chatter of this before in various places in Tas. I have had it on Hartz Peak, same deal but it swung around and wouldn't 'stick'. But I knew where I was so ignored it.
Next time I checked the compass a week or so later all was well. I also heard a story of this from Lichen Hill on the Tasman Penninsular. Seriously charged dolerite apparently.
In another interesting experience, I was on top of Hill 2, Moonlight Ridge when ILUVSWTAS checked his GPS our altitude was fluctuating by 30-40 metres every second or two!
It was blowing an absolute gale and we put the reason down to the extreme wind. This stayed like this for at least a couple of minutes, that is until he lost his beanie into the valley behind us
