KS-10 'Charger Problem'?

I have read brief reference to the ‘charging problem’ with KS-10s in multiple threads, but have not found a discussion about it (i.e., "they work well for me, except for the charging problem . . . "). I may have this problem, can someone please describe what is apparently a known issue, what steps to remedy it and if it is something that can be satisfactorily resolved? The issue here only affects one hearing aid. The other one works fine, but both sit in the charger, light turns green (charged), but then either only one hearing aid works and the other does not, or both work for a few moments, then only one works. Put the non-working back into charger and it is yellow (not charging).