LB1121 Randomly Changing MAC address

[dmckibbin]

I have a LB1121 4G-LTE modem which is mostly great, but there is one annoyance. The MAC address does not appear to be static. It seems to randomly change. Sometimes once a day which causes connectivity to drop for a few minutes. Also I'm trying to point a default route to it for IPV6 with the link local address and that also seems to change randomly. Is there any way to change these two behaviors? It doesn't look like there are a lot of user configurable options from what I can tell.

[schumaku]

Based on the description one would assoume you talk of the LB1121 router mode.

Can't help much, as the Swiss mobile providers don't offer any IPv6, and we deploy our units in pure Modem mode.

[dmckibbin]

Yes, it's running in router mode. Maybe I'll try it in bridge mode and see if that works any better.

[schumaku]

This is delegating all NAT and routing jobs to an additional device then.

[dmckibbin]

Yes, I have a firewall behind it.