We're building a media-installation with 5X Analog micropone and 5X digital IR sensor on an Arduino board with Flash interfacing. The audio sensors work perfectly with a zero value when there's no sound and about 180 when you talk into them directly.
So far so good but when we hook up the ground for the digital sensors (Infrared) everything starts to go wrong. The IR works but it causes a major disturbance in all the channels both analog and digital.
We tried splitting the ground cables between analog and digital and re-checking every connection but that doesn't seem to be the problem.
Since the digital signal triggers an engine it would be nice if it actually processed the right data. If anybody has some info or a good idea what this problem is about please let us know, time is running short on our deadline.