In my experience, the DASH clients on older devices are insane. If those devices are important enough, then you need to make playback work well on them. It kind of doesn't matter what the problem really is.
This can ALSO be an issue with poorly implemented DRM, btw. I've definitely seen certain popular settop boxes blow up when fed streams that were 100% valid within the constraints of the Main10 profile @ level 5 (both vbv limits and MaxDpbSize). Reducing the reference frame count was the only solution. This was acknowledged as a firmware bug but I don't know if it's ever been fixed
