Akiyamas tend to flog out cam-followers on the impression cylinders without VERY strict maintenance schedules. Often it will manifest as slight doubling of image-especially on lighter stocks.
Get them to run some heavier gloss stock (150gsm+) then try lighter and lighter stocks. If you've got a cam-follower on its way out gain and doubling will increase as the stock gets lighter.
You may be able to feel some slop in the bearing by unloading it and wiggling it a little: if it moves, it's toast. If it's really bad you'll be able to tell by eye: it will be discoloured and not roll smoothly around the cam.
Bear in mind that each group of 3 impression cylinders services 2 plate cylinders so 1 blown cam-follower will show up in 2 print units. If EVERY unit is showing the exact same issue it's a possibility that it's had a decent smash at some point and may have damaged something more serious.
Hope this helps a little
Just get on with it. Its as simple as that.