I have found what was wrong. For some reason, I had an option "Round screen display to 0 decimal places" on at Tools>Options>Precision. That will obviously cause some weird things. :)

Thank you for your help!

JasperC

Thank you, that seems to be a (straight-forward) step in the right direction, but I'm not there yet.

When I insert evalf(solAC[1]), I get to see 1. as a result. One point what, exactly? :s

Also when trying for example evalf[5] (solAC[1]), which should give a numerical solution containing 5 digits, gives '1.' as a result.