December 2018 version of HP Spectre 360 laptop with 4K NVIDEA GEFORCE. Hooked up to HP Z27 4K monitor thru HDMI works fine. Just introduced a CKlau brand KVM switch (4K 60hz HDMI HDCP EDID) and now getting random blank screens only for this laptop (Dell Latitude E5570 is ok). Obvious though is kvm switch but having trouble finding decent one don't want to spend $300 more a better KVM only to have it happen again. Tried various cables but seems to still be happening.