it's difficult to say exactly why the packets are getting duplicated. However, one of the reasons could be that Omega AP has the same IP range as the router (ifconfig should tell you if this is the case).
Might be also worth connecting to your router with another device and pinging the same host to ensure that the router is not at fault.
@Guest In the ping command, "ping -c 1 -W 1 downloads.openwrt.org" there are the two parameters - c1 and W1. The number after the "c" is the amount of pings sent and the number after the "W" is the timeout in seconds.
In this case, I have asked for one ping and to wait 1 second for the reply.
Looks like your connection to Community was lost, please wait while we try to reconnect.