Perhaps somebody out there can help me identify a problem with my Bronica ETRs (that's ETR x 2, not ETRS x 1). They've both developed intermittent shutter failure with their magazines on. When I test them without mags they fire every time, with every lens. But with mags fitted (and still in multi-exposure mode) the shutters fire sometimes OK, sometimes with noticeable lag and sometimes not at all. Strangely, the problem appears to have arisen simultaneously with both cameras. Has anyone else experienced this? Is the problem likely to be the camera bodies (the spring driving the communicating pin between body and mag becoming fatigued and not firing strongly enough)? Or are the magazines the likely offenders (the mechanism behind that pin developing too much resistance due to breakdown of lubricant or gunk build-up)? I believe that the lenses are "innocent" because the shutter actuating levers (inside the bodies' lens-mounts) are sluggish over the last few degrees of their travel (which is when the shutter would be tripped if a lens was on) with a magazine fitted. However, without mags the actuating levers seem strong and fast. Any suggestions would be welcomed, please!