         if cur_sample and (offset - prev_sample.time) * direction > (cur_sample.time - offset) * direction
             index += direction
         index
-    next: (direction=1) ->
+    next: (direction, jump) ->
         return unless @valid()
-        @offset += @jump * direction
+        @offset += jump * direction
         @start = @find_closest_sample(@get_start(), @offset, direction)
         @end = @find_closest_sample(@get_end(), @offset + @span, direction)
         @reading.unhighlight()

            return true if $target.is('input')
            switch evt.keyCode
                when 37 # left
                    fixfix.data.reading.selection.next(-1)
                    stop(evt)
                when 39 # right
                    fixfix.data.reading.selection.next(+1)
                    stop(evt)





class Selection
    constructor: (@reading) -> # half a second default jump
        @clear()

    clear: ->
