The veneer on these cases is very thin so a chemical strip is the only way to remove the finish without damage, sanding is very risky. I have had success using a 50/50 mixture of lacquer thinner and 90%+ alcohol. Apply liberally with a cotton rag, it will strip the old finish and remove any tinting back down to the bare wood without causing any damage. Re-coat with 2 or 3 coats lacquer or tint first and then lacquer.