Weird Packet loss

I have set up a Wireless network N-Only between to RB800 and my TCQ is 95% with data rates of 70Mbps, When I try Ping anything on the Internal network (Between the wireless link) Ther is absoultely no Packet loss, but when im on the Routerboard which is wireless connected to the rest of the network and I try Ping anything on the internet I get 20% packet loss

Do anyone maybe know why?

Need more info.

What cards/frequencies, how long of a cable run, are you connecting wirelessly by a laptop, CPE, etc?

What is your signal strength on your wireless test?

What is your Internet connection?

How many cards in your RB800?