Contacts between robots and environment are often assumed to be rigid for control purposes. This assumption can lead to poor performance when contacts are soft and/or under-damped. However, the problem of balancing on soft contacts has not received much attention in the literature. This paper discusses four approaches to control a legged robot balancing on visco-elastic contacts. Two of these approaches are novel, whereas the other two are taken from the state of the art. Our simulation results show that no approach can outperform all the others in all situations. Performance heavily depends on the contact stiffness and the noises/uncertainties introduced in the simulation. These results sheds light on this challenging problem, while pointing out interesting directions for future investigation.