Low hashrate on 1060?

I installed 2 x Nvidia 1060 with 6 Gb each. When using multiple different miners, I end up with a low hashrate such as 10..11 MH on each, totaling around 20 MH, but fluctuating very strongly (to the downside.)

I first used Minergate, and dismissed it soon for its low hash rate (which was a wrong assumption.) Turns out I only needed to upgrade the BIOS firmware of my Asus V270-K motherboard. Upon restarting Ubuntu and powering on Minergate, I now get a constant 44..46 MH, which can be considered good for an untweaked, untampered pair of 1060’s.