Re: Important Rod question...
I've never had that problem with the 40-odd single-hand fly rods I've owned (although I've occasionally shaken a tip section loose, which is disconcerting when it goes sliding down my fly line and into the river). If wax doesn't work, contact the manufacturer.
Spey rod users are advised to tape rod sections, to avoid the loosening caused by a spey rod's powerful torque. I do so, and it's easy. A section of electrical tape, wound in a spiral an inch above and below each joint, keeps them in place. A piece can be reused 6-8 times and can be wrapped around the rod section between uses. It takes just a few seconds for each joint.