Proxy arp - 50 % of packet loss

Hello there.
I was trying to make a simle vlan per user scheme on vyos 1.1.8. There is a single public network which I want to spread across few VLAN’s and I test this config:

> vyos@vyos# show int
>  ethernet eth0 {
>      address 83.246.163.100/24
>      hw-id 00:1d:60:5b:86:6d
>      vif 11 {
>          ip {
>              enable-proxy-arp
>          }
>      }
>      vif 12 {
>          ip {
>              enable-proxy-arp
>          }
>      }
>  }
>  loopback lo {
>  }
> [edit]
> vyos@vyos# show prot
>  static {
>      interface-route 83.246.163.11/32 {
>          next-hop-interface eth0.11 {
>          }
>      }
>      interface-route 83.246.163.12/32 {
>          next-hop-interface eth0.12 {
>          }
>      }
>  }
> [edit]

83.246.163.11 resides in VLAN 11, 83.246.163.12 - in VLAN 12, eth0 is connected to a trunk switch port.

And it is working pretty bad. Machine 83.246.163.11 can reach 83.246.163.12 and vise versa with no problem through my VyOS device. But if I try to ping 83.246.163.100 from 83.246.163.11 (for example) I get about 50-70% of packet loss. The same thing if I try to reach some devices behind the VyOS from 83.246.163.11 or .12.
The only thing that is working good - that 11 can reach 12.

Is the problem with proxy-arp mechanism or what? There are correct arp records on .11 and .12 machines (83.246.163.100 corresponds to eth0.11 MAC in case of .11 and eth0.12 MAC in case of .12).