Zeiss 3 way beam splitter - double image

[MikeBradley]

I recently purchased this Zeiss 3 Way Beam Splitter with drawing attachment (part 47 30 51). The plan was to use it in outreach with cameras and the drawing attachment. It appeared to be in pristine condition externally and the vendor had described the optics as excellent. When I use it in straight-through mode the images are sharp and clear but as soon as the beam splitter is in the light path the images are doubled laterally. What could cause this? I suspect that the beam splitter is misaligned, if that is the case, is it feasible for an amateur to repair this sort of defect?
Thanks
Michael

[MikeBradley]

Unfortunately I didn’t get any responses to my original posting.

I’d originally had great hopes for using the beam splitter at outreach events, but I’m now considering returning the faulty unit to the vendor and trying to find another one. In other respects it is in near mint condition and I could use it for some applications while I try to fix the misalignment. Is it feasible for an amateur to repair this sort of defect? If so, where might i find how to?
Thanks
Michael

[wstenberg]

Michael,
Probably no one has ever had one of these open before. Difficult to guess what might be wrong. My guess is something has come loose or fallen off. Be sure to post if you figure it out.