Everything I've seen boasting greater than 54Mh/s have been changing the OpenCL worksize and causing invalid shares that reduce effective hashrate back down to around 50-54Mh/s.
Exactly that. 1300/915@0.85 gives solid 51.5mh/s. If you increase worksize then reject rate increases to 10-20%
@claymore
Strange stuff regarding 380 hashrate reporting with v15. Just updated drivers from 18.6.2 to 19.10.1 and miner reports 380 hashrate at 37mh/s+.
Phoenix is still fine with ~19mh/s, which is the true hashrate of the device.
Fury hashrate reporting is fine. Not sure if it happened with earlier versions of the miner or previous 19.x drivers.
Decrease 0.85 to 0.75. You don't need 0.85