'Side were looking to bounce back from Wednesday's loss at home to Frenford, but fell behind after ten minutes.
The score remained that way until half-time, with Burnham wrapping the game up with goals on 64 and 72 minutes to ease to a 3-0 win.
The result leaves 'Side in 14th place in the league table, whilst hosts Burnham climbed up to top-place in the table.
'Side are next in action on Wednesday 31st August when they host May & Baker at Cricklefields. Kick-off for that natch is at 7:45pm.
'Side: Hayden West, Jordan Cornelius, Bradley Gayer (Nathan Saunders), Shaquel Foyewa (Quincy Warner), Josh Peach (Joshua George), Elliot Scott, Codey Cosgrave, Demi Elegushi, James Ross (Taylor Tombides), John Gilroy (Jack Gibbons), Dan Jones