IR LED + Arduino mega 2560 + ethernet shield

Hi guys i have purchased Arduino Mega 2560.
I had arduino duemilanove with this sheild ethernet

I have used iRLib for switch on my AC or TV. (with Arduino duemilanove)
Now, if i connect the ethernet sheild, it work on pin9 but my AC doesnt switch on...
I have see with a camera the led, and it send the code slow / delayed...
but with arduino duemilanove it work very fine!
Why??? is the timer? i don't know...

static const uint16_t OFF[] PROGMEM = {4492,4432,592,1608,588,508,596,1604,588,1608,596,504,588,512,592,1604,600,500,592,508,596,1600,592,508,596,504,596,1600,596,1604,588,512,592,1604,592,508,592,1604,592,1608,596,1600,596,1604,588,508,596,1604,588,1608,596,1604,592,508,592,508,596,500,592,508,596,1600,592,508,596,504,596,1600,596,1604,592,1604,600,500,592,508,592,508,596,500,592,508,592,508,596,504,588,508,596,1604,588,1608,596,1604,592,1608,596,1600,596,5264,4524,4424,592,1608,596,504,588,1608,596,1604,592,504,596,504,600,1600,592,508,596,500,592,1608,596,500,592,508,596,1604,588,1608,596,504,588,1608,600,500,592,1608,596,1600,592,1608,588,1608,596,504,588,1608,596,1604,592,1608,596,500,592,508,596,504,596,500,592,1608,596,504,588,508,596,1604,592,1604,600,1600,592,508,596,500,592,508,592,508,596,504,588,508,596,504,596,504,588,1608,596,1604,592,1604,592,1608,596,1600,592,1000}; //

void ReadFlash(const uint16_t *x , byte len){
  unsigned int buffer[256];
  for (byte i=0; i < len; i++) {
    buffer[i] = pgm_read_word( x+i );
  }
  My_Sender.IRsendRaw::send(buffer, len, 38);
}

On arduino duemilanove is... OK! but with mega and ethernet sheild doesn't work.
If I remove the ethernet sheild and insert the led on pin 9 of arduino mega, it WORK.

"Doesn't work ONLY with ethernet sheild attached"

Sorry for my english... only you can help me... Thank you!

Upppppp :frowning: :frowning: :frowning:

nobody knows anything ?
See the comments.. Ubuntu Pastebin