Fault analog input channel

Hola, I'm new to the forum! Anyone else from Ohio?

Any who, I use a lot of Festos CPX line up for my remote I/O. Lately I've been having an abnormal amount of analog input channels failing on me! Most of the time they decide to stop working after I finish the install and fly 3,000 miles back home!

Ironically the last 3 analog input cards that had channels fail were all on the west coast and in the last 2 months after the install.

In you experience, what was the root cause to having channels fail in your situation?

So next time you check in for the flight, but don't take it, Festos will think you're 3000m away and will fail,just in the moment you show up from the corner. It sounds good to me, so I drink beer if it works.

I have couple of them, working couple of years with no issue. Try to give some more details for troubleshooting.
Are all fails on one rack?
Are all of the fails on one power supply?
Are they connected to similar equipment, different than the ones that don't fail?
Are there any cables running in ducts along with high voltage or other noise producing devices, VFDs, motors, transformers,etc.
Just try to find some pattern, as I haven't seen lot of analog modules fail just like this, usually the reason is external.

what was the failure mode? card status light shows fault? one channel bad? all channels bad? signal pushed off scale?
what are the signals, 4-20mA?
if 4-20mA, active (powered by the field device)?
if 4-20mA, passive (powered by a separate DC power supply?
shielded cable?
shield grounded where?
length of cable runs?
Signals come from what types of devices?
model number of the AI card?
Is the location subject to lightning storms?