Cassette deck help

[colinc1968]

Can anyone help I've a Yamaha K-340 deck and after about 3-5 minutes of playing a tape it starts to speed up then slow down and then completely stop...is it worth getting repaired or buying another one...new is out of my price range so it's got to be second hand....I've seen a technics rs-b40 is this a good reliable machine for its age....or can anyone recommend a decent second hand deck or website...any help would be much appreciated

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