The Commodore range of computers (Vic16 C64) had dedicated cassette players that I believe were made by Commodore but the Dragon computers relied on standard cassette players for playing music etc. Balancing the output from the player (volume and tone control) was critical and it took me 5 different players and a very friendly electrical shop owner to find a compatible one. Even this was at best hit and miss.
Another thing I remember well was typing in machine code from magazines to get a small program to run. You know what I mean Nigel, 11000110 10100011 11110000 10101010 and so on. Hours or even days of effort and after debugging all you got was a flag waving on screen or a matchstick man walk across the screen which probably lasted about 10 seconds.
Still had loads of fun doing it though.
Alan