blocked DNS problem

I have the following senario:

1 WAN cable (60Mbs) with DHCP Client
1 WAN ADSL (10Mbs) with PPPoE Client
3 LANs: 2 with separate APs and one computer on the 3rd LAN

WANs being handled by PCC

If I disable the cable adapter all works fine but with both (or just cable) working the DNS requests do not get answered.

If I reset Mikrotik and get it working with factory default the cable works and DNS requests get answered.

MikroTik RouterOS 6.30.2.
RB750 with firmware 3.22

Any suggestions ?

The script is attached