FireTV on vlan - stops playing after 1-10 min

Server Version#: 1.42.2.10156
Player Version#:
<If providing server logs please do NOT turn on verbose logging, only debug logging should be enabled>

FireTV on IoT netwok, server on Internal network

i have allowed access to my plex server (ip/ports) with firewall rules on my unifi controller (zone based), also enabled mDNS on both networks

i can fire up the plex app on my phone via the same wifi, to the same access point and i can access my plex server and play complete videos without issue, but on the FireTV it will only play for a few minutes, then black screen and busy widget

i have signed out of both the app & the server, unistalled/reinstalled plex on my firetv, i see my firetv as an authorized device on my plex server

i noticed a difference in the server logs

Request: [192.168.20.151:42404 (WAN)] - IoT network

Request: [192.168.13.154:41308 (Subnet)] - internal network

i thought with the firewall rules i would see Subnet for both, but i looks like when on the isolated vlan it is accessing server from WAN?