Run a sequence through your camera where you start at a small aperture and slow shutter speed and change that by a stop till you run out of aperture/shutter speeds. Should be all the same exposure if you brighten by one stop and reduce exposure time by one stop each step. Gotta make sure it's being exposed uniformly.

When developing be absolutely boringly consistent in agitation and tell us how that works. Is it straight d76 or 1:1? If it's the same batch of developer from last year, it could be going bad depending on how it's stored.