Hello, I just purchased a vintage harmony ukulele, and it came with wooden tuning pegs. I purchased it off ebay, so I was anxious about the true condition of the uke. It's in nice condition, but I noticed that when I turn the tuning pegs, two of them wont stay in place. I'll turn it to try to tune it, and it'll twist back really fast to where it was. Like a rubber band, almost. So I was wondering, if I bought newer tuners, would this solve the problem? Can you put metal tuners, such as these http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT on a vintage ukulele? Any help would be much appreciated!