Gadolinium gallium garnet (GGG) is a frustrated system which has already been successfully studied using muons. This study extends the earlier work to high magnetic field and will (i) provide a good test of the capabilities of the HiFi spectrometer for performing spin fluctuation decoupling and (ii) provide insight into the nature of the spin fluctuations and field-induced states in GGG. Because GGG is strongly frustrated, low-energy (i.e. low frequency) modes are crucial in characterizing the ground state and the earlier muon studies failed to decouple them (insufficient field). We know what we are looking for because of the earlier studies and so we can home in on the key temperature ranges which delineate the behaviour [see I. M. Marshall, S. J. Blundell, F. L. Pratt, A. Husmann, C. A. Steer and W. Hayes, J. Phys.: Condens. Matter 14, L157 (2002)].