WhatsApp sending images more than once


Many times (more often than not) when I take a photo and send it to someone with WhatsApp, it sends the picture. Then when I go into WhatsApp again, for example to send another message or read a message, it sends the picture again. This is happening on my Galaxy S3 now, and has happened previously on my HTC Wildfire. Needless to say, this is pretty annoying. Anyone experience this before?