Strange reprap discount LCD panel issue

Hey everyone,
So this has been a strange issue I have been facing on my new custom made delta. It is a full metallic body.

Issue and observation:
The print starts well. And all of a sudden, the nozzle starts going into the part. After observation, I found that the Z coordinate on LCD panel is 0.00
So at any point of time, for any file, using simplify3d or Cura, the Z coordinate suddenly becomes 0.00
I have attached image URL for the same.

Images:





My initial thought was a gcode error. I printed the same gcode in a different machine. And the print came out perfect. So this isn't because of gcode.

Things that worked:
1) Assuming, the error is because of LCD panel, I printed the same part via USB, and this time there wasn't any occurrence when the Z becomes 0.00

2) I removed the LCD panel from the metallic mount, and placed it on empty spool of filament. Amazingly this worked too and got a perfect print. So that makes the LCD hardware fine. Now I mounted the LCD panel back, and the issue resumes. All of a sudden during the print, the nozzle wants to move at Z0.00

Reason ?
So the machine works fine if I print it using USB or keeping the LCD panel on an insulator like wood or plastic.
But mounting the LCD panel back on metal frame brings the issue back. I have made sure that, no electronic part of LCD gets in touch with metal. The only thing that brings the LCD panel in contact with metal frame are the bolts. So my question is, what can be the reason behind this strange behavior ?