Spins on the kagome lattice are one of the most widely investigated topics in frustrated magnetism. This two-dimensional corner sharing triangular lattice offers a macroscopically degenerate ground state if the lattice symmetry remains unbroken, and fluctuations persist to the lowest measured temperatures. Na4Ir3O8 represents the three-dimensional analogue of these systems, the hyperkagome lattice. It has spin-1/2 moments and with no magnetic order observed down to 0.3K there is considerable theoretical work describing it as a spin liquid. Recently other theories have suggested it is a valence bond crystal. muSR provides an exquisitely sensitive probe of spin liquids and we propose to extend our previous measurements (T>0.3K) to dilution fridge temperatures and also use the approach recently shown to be successful in k-ET2Cu2(CN)3 for finding phase transitions from the spin liquid state.