Can anyone tell me why you often hear African/Jamaican people saying 'arks' or 'aks' instead of 'ask'? i.e 'you only have to aks'. Is it deliberate or a dialect difference?
Even within British English, the forms 'ascian' and 'acsian' existed side by side at one time. The latter gave rise to 'ax', which was commonly used until the 1600s and thereafter used in various British dialects as the normal form of 'ask'. I'm not certain, but I wonder if it is possible that British explorers, missionaries etc who first went to Africa actually took that form there with them. It would, after slavery, have been natural for it to be common in the West Indies, too.
I think it might also be worth considering that people who acquire English as a language often put their own twist on it as well which carries over from their own language. For instance, if you look at Ireland and England, although we speak a common language, the Irish have their twist on it.