[natesully]

I'm trying to get Audio up on the Cyclone II starter board as a small experiment. I added a debug pin to probe the LRCLK signals, and doing so made the thing work - removing this pin will cause noise to be added to the loopback audio signal. Anyone have ideas as to what could cause this?

I'm an absolute begginer to FPGAs, I managed to get RS232 and I2C up earlier. This just seems to be giving me extra trouble...

In the image, VGA_B[0] is the offending pin. Changing it to other pins near the audio ones results in things still working, picking a pin far away (like GPIO_1[15]) or removing it causes the noise.