You are right, but I thought maybe ask here as here should be people using both versions, docker or plugin; and what people thinks is more stable.
Anyway, if someone with the same problem read this, I fixed it changing the Tvheadend's CA mode from "Oscam net protocol" mode to "Oscam TCP" mode.
Plus for DVB driver reference: I'm using a DVBSky S952 Dual DVB-S/S2 PCIe (V3) with LibreELEC Driver-package. Working perfect.
One more time, thanks ich777.