Hi and welcome to Frog Forum

Ryan is right, the frog is in the genus Kassina, however the species is senegalensis - known as the bubbling kassina. There are two species of Kassina in SA, but the bubbling kassina is the only one that is found in Gauteng. This frog is often mistaken for Weale's running frog (Semnodactylus wealii). Their range covers much of sub-Saharan Africa. The males have a awesome call that sounds like a very loud bursting bubble

Their habitat consists of grasslands near bodies of water such as vleis and pans. There are many species of frogs and toads that inhabit residential areas.