Cheap and easy fix for lens
If it is the lens, the cause is oxidation. Get Meguiars Vinyl Cleaner (#17). It has a fine rouge in it that will polish away the oxidation and make it look like a million bucks.And you don't even have to take the compass out.Seen it work many times. Same stuff that works incredibly well on our old '85 H34 windows that we originally thought we would have to replace.It works on dodger glass for scratches and the ports. Follow up with the polish as described below. One bottle will last many years.Here is the info from Meguiar's web site:Mirror Glaze Clear Plastic Cleaner Safely removes hairline scratches, dirt and grime. Clear plastic that has lost its clarity due to significant contamination and fine scratches should be treated using our two-step process. Meguiar’s non-abrasive, alcohol-free Plastic Cleaner aggressively cleans and removes scratches without harming the surface. Follow up with our M-1008 Plastic Polish for a perfect finish. M-1708 ....................8 oz. $6.25 add to cart You can obtain the product at West Marine.