some broadcast packets lost in bridged setup

Hi there,

I am experiencing a broadcast packet loss between a client connected to a SXt2 and the AP (Basebox 2).
The SxT2 is configured in station bridge mode and connects to the AP just fine. Both are on RouterOS v6.36. AP is configured in AP bridge mode.
Signal is very good and bandwidth test is in excess of 100 Mbit/s both ways.

So I run tcpdump on the linux box who is sending broadcast packets on UDP port 57900 (this is a protocol to control LIFX smart wifi bulbs).
If I connect with my linux box to the AP and run tcpdump there, it seems that about 20% of these broadcast packets do not reach my linux box.
This seems to happen more often when the sender sends 3-4 broadcast packets in a row.

All ping tests I have ran showed no packet drops so it doesn’t look like a media problem to me.

Any tweaks I could try to see if I can improve broadcast redistribution by the AP?
Any hints where to look here?

Thanks in advance for your help!

Rick