Riley burwat 1piece cue sound problem

I have a old steve Davis Riley burwat 1 piece cue.. Owned this now for nearly thirty years.. It started making a horrible noise a few months ago like a ping or a hollow noise when I struck the ball, I've had two ne Ferrell and half a dozen tips in the last 18 months.. It seemed to be ok after the last tip and Ferrell but has started doing it again.. I've tried shaping the tip a little and sometimes when the tip is buffed a little to add more chalk it stops.. I'm wondering if it could be a crack in the cue? Or maybe the weight? I can see the bottom of the cue where the weight is but no movement like it's moving up and down? Any help or advice would be great...

Riley burwat 1piece cue sound problem