It was never actually hashing at that rate, it was incorrectly reported by bitmain's cgminer fork. Did you ever compare the reported hash on your end to what the pool you were mining to saw?
Yes, I did, the pool also reports ~72-75Gh/s, continously... And it´s the only miner I have running, so I guess it´s true
![Wink](https://bitcointalk.org/Smileys/default/wink.gif)
I have now found and compiled the bitmain fork and I am back at that rate with the raspberry... All good
![Cheesy](https://bitcointalk.org/Smileys/default/cheesy.gif)