This noise has occurred in my H22a7 before now, but probably first happened a good two months ago. It's since happened a few times recently and generally after short runs when the engine just gets up to temperature (Although I've not done many long distances recently), and it only sounds on idle (or only just above). I can certainly feel the vibration when I touch the valve cover. The car isn't experiencing any performance issues either. I'm suspecting the LMAs, but the H22a7 should have the coil/spring type ones right? Surely they shouldn't be sticking?

...
Apologies for whatever sounds like I'm tapping on the mic. My phone hasn't captured the noise amazingly. You can hear it at 10 seconds and 30, and then 38 seconds and 49 when I let off the revs...
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This guy has captured the noise better, which is really evident from 37 seconds onwards...
[youtube]CLfACGEWGWg[/youtube]
I'll have to remove the valve cover over the weekend if I get chance (Probably won't

) to see, but otherwise what a pain!
Any thoughts?...