Well the 1.05 at those settings seem ok ... but why it drops to 0.45 with the lower clocks is strange - can you tell me which hive image you run? (I would pick the beta one, since this has amdgpu-pro 19.30 driver. Also I do not know if hive already pushed 0.9.2 final to their repo)
hiveos-vega-0.6-01@181121 VEGA
Linux kernel 4.15.18-hiveos
amdgpu-pro-19.30-934563-ubuntu-18.04.tar.xz