Modified laptop power supply pulses - voltage too low?
The clicking sound you hear is coming from transformer. If you hold tight the ferrites with your hand then you'll see that the click sound will be lowered.

I personally don't recommend decreasing the output voltage of a flyback converter like you have to such a low voltage. Because its transformer is designed to provide about 19VDC. Playing with feedback resistors can be acceptable for a little change. But you decrase the output voltage about %74! If you really want to get 5VDC, you should also un-wind a few turns from secondary of the transformer.