Hi everyone
we design and produce touch WIFI smart switches. there are a touch sensor (BS814a), an ESP8266, micro stm32 , Buzzer and ... there are different issues we are encountered from time to time. one of them is ghost touch on an specific pole for example the 2nd pole of a 3-pole switch. and the other problem is as a result of some changes in our pcb tracks, suddenly our switch doesn't work properly with 3mm glass(overlay) on it, but it works with 2mm glass. it didn`t have any problem with glass thickness till last month. now I want to know how pcb and its track impact on capacitive sensitivity and how we can fix it? could you help me plz?

 

The TS is asking for free engineering services in the product development part of a for-profit company. So any assistance will bring them a real financial benefit, since the last change that they made stopped one product from working.
Aside from that, a symptom is presented without enough context information to allow more than a random guess at a possible fix.
So a non-guess suggestion id to understand how the circuit functions and then understand what was changed and how that relates to the circuit operation.