router help

Hi I have a 60 Mbps internet and have a ea6500 linksys smart wifi router.  when I hardwire into the router I get about 36 Mbps but if I bypass the router and speed test i get the full 60Mbps is there a setting I need to look at on my router to fix this.  I am very new to this and the internet company tell me its a router issue then but I was told when I bought it that this one would handle it no problem