I use 2 portals on the Formuler box.
The one works good. The other one when you switch from channel or go to another category it suddenly loads the portal again or goes to the home menu. This happens often.
I tried the portal on the Z Prime, Z+ & Z Nano.
The Z Prime & Z+ goes to the home menu and Z Nano starts reloading the portal.
The box has the latest firmware and MYTVOnline and this problem since a long time.
I tried the same server on other devices like MAG and didn't get any issues.