I have an ZWO ASI120MC (the chinese clone Datyson T7) as a guider camera. Strange thing appears with the viewer in Ekos. My screenshot describes perfectly what appends.
I tried with the official ASICAP software and everything works fine.
I'm using Ekos with the ZwoCCD driver SDK version 1.14.0315.
Linux Mint 19 Cinnamon using PPA for latest KStars-bleeding and INDI
Raspberry Pi 3 B+ with StellarMate
Atik 314E - ASI120M - CG5 with Celestron C9.25