VDO Tachometer Issue 2004 34 Pilothouse

I have a 2004 Pilothouse Sedan and have an issue with both of my tachometers at various times. A few times after opening and closing the helm if anything was pushing against the gauge it would either stick at various times or altogether. If the what was causing the pressure on the back of the gauge was moved out of the way the problem disappears. The startboard tach, if sitting in direct sunlight for a long time it does not go up when increasing speed. Once out of direct sunlight by either altering course or shading the gauge the problem goes away. Has anyone ever experienced something like this before or heard about this type of issue? I searched the forum by using VDO* in the search bar and have not found anything close to this situation.