Sorry for the delayed reply, but I am very thankful in saying that I have now got the sound working properly through both speakers.
The culprit of the problem was in the cable I was using. After purchasing a new one from amazon I am getting 'clear' enough sound from a cassette from both speakers.
Its funny though that when I went to test the cassette in my ghettoblaster I inserted it into the right cassette slot, I usually use the left one but as their was a cassette already in that slot I thought nothing of it and used the right. The sound came out of both speakers but sounded muffled, I was very disappointed. But after further investigation I have found that the right cassette slot play's back muffled sound while the left one is clear, so in the end the recording was fine just my equipment was the problem haha.
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