Both hot and cold tub knobs leaking behind the wall

Okay, so I may have solved this problem but I want to know if my solution even made sense. We recently bought a house and soon realized (due to the ceiling being soaked downstairs) that our upstairs bathtub was leaking. I figured out that the leak was dripping from both the hot and the cold knobs inside the wall but only when the water was turned on and running. I removed the spout (which was on pretty darn tight) and continued fiddling and realized that the water was no longer dripping inside the wall and there was also no more water downstairs on the floor while running the water. So I reapplied the spout but did not tighten it to the point where it was so tight that the handles moved towards me.. and it’s still not leaking.

So I guess my question is if the spout is on too tight can it cause the handles to leak water behind the wall?

I don’t know if this is a completely stupid question but I let the shower and spout run full blast for 15 minutes after loosening the spout and there is no water dripping and my floor downstairs is dry.

Thanks so much in advance !!!!