We investigate low resolution spectra and the Balmer line profile in particular of the Active Galactic Nucleus associated with the X-ray source RX J0818.2+0122, and also compare this to an archival Gemini spectrum recorded seven years earlier. This AGN displays broad emission lines with a double bump profile that is characteristic of fast moving gas in a Keplerian orbit around a supermassive black hole. This source is particularly interesting, as the rotational speeds inferred from the line widths reach 15 000 km s$^{-1}$, which corresponds to some of the highest values measured in AGN with Keplerian rotator line profiles. We attempt to fit the profile with models developed for this class of objects, and thereby estimate the dimensions, inclination and some additional properties of the broad emission line region of this AGN. Our study highlights a significant weakening as well as considerable profile changes in our latest spectrum. Given that this AGN is also a radio source, we explore the possibility that the peculiar broad line characteristics are related to a radio jet.