Story time. I bought one of the first BMW E93s back in '07. One of the options I bought was the iPod connector. Turns out it didn't work right for me and many other owners as it would randomly stop playing the iPod and switch to FM. Oddly some owners did not have this problem. Others were able to get a new module installed which reportedly solved the issue. But early on in the situation BMW stopped authorizing replacements saying it was a software issue. I thought that was unbelievable since new hardware fixed the prob. Also it didn't affect all owners.
We'll a couple months later BMW finally issued the s/w fix. I took my car in, but I was skeptical it would work, and ready to raise Caine b/c I was beyond fed up. But you know what -- the s/w fix worked. I don't know how, but I never had the problem again nor did anyone else report an issue.
So lesson here is that s/w can play funny tricks to make an issue look h/w related when it's the s/w the. whole time.