If converter_->open() fails, the code deletes the converter_ but then happily goes on, and at the very next lines will use converter_ to connect the bufferReady signal. Ensure the converter is only connected when successfully opened by extending the conditional and connecting in an else scope instead. Reported-by: Tomi Valkeinen <tomi.valkeinen@iki.fi> Signed-off-by: Kieran Bingham <kieran.bingham@ideasonboard.com> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>