Thomas,
I know this thread is ancient, but just wanted to let you know that dozens of peeps experienced the same palpitation issues over on ‘inspire.com’ a year or two back, at least when they were taking the MK7 (and I think MK1?) versions — but like you, found that they had no problems with the MK4 version.
I’d post a link, but they need your email and a password before reading anything on their site.