Remember the various posts about Wouxun handhelds losing memory contents? Although the chance of encountering this problem seems to be remote, it does happen. A small component (a 24C64 serial memory IC) can give up in time.
The good news: it can be repaired/replaced at almost no cost (about 60 cents). The bad news: you need to be comfortable with working on small components and must have the tools to do it. If you don’t, have it done by someone with more experience.
The complete repair guide can be read in detail on Mike Mercury’s, which is the website of Tim N8NQH.
Link to a Chinese eBay seller (10 pieces for $2.38): http://www.ebay.nl/itm/290951221455