Hi Mark, I have bought myself a nyunga nyunga 15 key Mbira. I bought a second hand one; from what I can gather and confirmed by the leaflet that came with it and its original wooden Box, it is an original Kwangoma Mbira and in good condition. So far so good; I began to tune it, and all the tines on the lower row are in tune, but two of them sound really dull. Apparently, there are a few “tricks” to rectify the dull sound, but I am a bit unsure as to what to do. Neither of the tines are touching a neighbouring one, nor are they particularly loose or tight compared to the others. I have the same problem with a couple of the upper row tines. Any advice as to what to do? I’m loathed to just tweak around and doing damage to the tines. Thank you in advance for your advice, Jens