Vibra-technics engine mount failure

[MTBMartin]

I've had a Vibra-technics engine mount set on my S1 Elise for around 3000 miles and the right hand (engine side) mount has failed. Not stripped it down yet to see what's happened internally but it's started knocking loadly so re-fitted the OE mount before anything catastrophic happens.
Apparently lots of talk about this on Seloc but can't log in to their forums at the moment.
Anyone else suffered Vibra-technics failures?

[chucklebutty]

Lots of reported failures on Seloc. They snap.

VibraT may offer some support as they’d had a batch fail.

[MTBMartin]

I've stripped it down now and had a good look. Fortunately caught it before the bolt failed, but there is deformation in the underside of the aluminium cone where it contacts the steel sleeve inside the bush (pic below). It doesn't look like much but it's enough to lose the pre-load in the long M12 bolt in that part of the mounting which then rattles around in the sleeve. Second pic of the sleeve bore shows what looks like a thread but actually it's just marking from the major dia of the thread as it's been moving around. Without the pre-load, the bolt will be getting a lot of impact shear loading which will fatigue and fail it. Bolt still feels tight because there's a lot of threadlock in the joint but most of the pre-load has gone.
Short term, I'm just re-assembly with a new bolt and will periodically check and re-tighten it. Long term, planning to shorten the aluminium cone and add a steel disc to stop the aluminium deforming.
Seloc forums have examples of other failure modes and those will have different causes, so not totally straightforward!

[MTBMartin]

pic showing inside of sleeve...