Is my dimmer2 defective?

Hello everyone,

i noticed that one of my shelly dimmmer2's keeps rather high temperature on idle (52 degrees). The only difference between the others is that it resides in drywall as oppose to concrete wall. Installation inside the socket is exactly the same. What is the normal idle temperature you are getting with your dimmer2's?

I also opened it inside and one of the capacitors looks rather white (not sure whether this is normal)

Regards,