Thank you for the reply Damian!
Yes, as you can see there is a passband filter before the receiver. Changing the transmitting wavelength of the light source at the bottom left corner I run two different simulations. First having the “interfering” lightsource within the pass band (thus not filtered) and then moving the lightsource out of the pass band (thus filtering it out).
My question is why is the Q factor in both cases the same?