IP TV Box

Hi, experts!!
I hope someone find solution for my problem.
I have RB 951G-2HnD with standart configuration:
eth1 is WAN through PPPoE
eth2 to eth5 and wlan1 are LAN with internal addres 192.168.2.0/24

Recently I choose another ISP which deliver to me Internet and IP TV with IP TV box (NEXBOX A95X)
Everything is ok with Internet, but IP TV box can’t take IP from DHCP server.

When I connect TV box to RB951G the box can’t take IP.
DHCP server show offered, but TV Box is in offline mode.

Whem I switch off auto negotioation and switch to 10 Mbit half dulex the box receive IP but can’t download provisioning information.

I tried to change MTU packet size on Bridge LAN, change none/RSTP/STP but have not success.

I find temporarily decision when I connect TP - Link router to LAN ports of RB and configure TP-Link WAN port to receive IP from Mikrotik. connect IP Tv box to LAN ports of TP link and everything is OK.

Can someone what is my wrong?

Thank You