Gstreamer 1.0 issue with rtspsrc

I used version 0.10.6 of gstreamer to properly stream 4 live feeds of video through RTSP.

//testApp.h

  
ofGstVideoUtils gst;  

//testApp.cpp -> setup()

  
  
gst.setPipeline("rtspsrc name=source location=rtspt://admin:admin@172.16.20.210/defaultPrimary?streamType=u ! rtph264depay ! avdec_h264 ! videoconvert ", 24, true, 1920, 1080);  
	  
	gst.play();  

This code here worked flawlessly.

I’m trying the same under gstreamer 1.0 (1.0.9 windows builds) and it behaves oddly, it works only with one camera and not everytime, sometimes I just get a black screen.

Any idea?