Gideon Analytical Labs received several PCB that opened up on several of the I/O metal dome pads.
The three black circles are the time, status, and menu pads. The metal domes came out when the two switches were separated. These buttons are connected to an output. The insulator cavity (the black spots) provides space for the metal dome. The metal dome makes contact when pushed from the top switch circuitry to the bottom switch shown later. The arrows point to conductor lost from switch 2 when the two switches were separated physically. The top arrow caused an open in the bottom circuit (shown by the arrow in the next picture).
The base material is polyethylene terephthalate (PET) film polymer with a thermoplastic silicone adhesive. The two layers of material are sandwiched together to enclose the metal domes for turning on and off switches. The switches were not functioning due to a corrected misalignment which caused an open in the silver trace lines when the sandwich was separated.
Gideon Analytical Labs can analyze circuits, materials, interaction of materials, reconstruct the failure and suggest solutions that will correct the problem.