LED Matrix and Arduino Yun

Hi
I received a 32x32 RGB LED Panel from Adafruit and wanted to connect it to a YUN to receive the information to display from the web.
I tried first with a 8x8 LED matrix and everything was working fine.
Then I connected the 32x32 panel to the YUN and nothing worked. I did not received the result the test sketches should show, only some LED lightning up. I renewed the wires two times and also reset the YUN twice. Still no solution.
Now I connected the matrix to a Arduino MEGA and everything was working immediatly.
See videos.
http://deguenther.net/sn/led_with_mega.mp4
http://deguenther.net/sn/led_with_YUN.mp4

The sketch is very easy, see attachment.

Any idea what is wrong on the YUN?

Thanks for you help.

Regards
Ralf

testshapes_32x32.txt (2.03 KB)