getJSON和输入表单不更新图表

This has really been wracking my brain all day. I am using getJSON() to retrieve JSON data generated by a PHP file and then graphing it with DyGraphs. I know the PHP file works as I use it to generate an initial graph without sending it data. I can also go to the url of the request and see that the data is correct. When debugging I can even see that the GET request is being made and for a split second the correct data does show up on the graph. After this split second though the graph just resets. This all happens when jQuery.event.add.elemData.handle.eventHandle is being popped off the call stack. This has really been wracking my brain all day.