Let me first give a big fat disclaimer that I essentially know no German at all. Being an IPA junkie I just decided to read about German orthography and (epicfailingly) try to read out some German for fun.
I have a problem with the long E (/e:/) sound. I hear it as /i:/ in some words and /e:/ in some words, but nothing I can find supports this. For example, by all spelling rules, and even by the pronunciation key in my dictionary, "Heer" and "hehr" are homophonous and pronounced [heːɐ̯].
Somehow, I hear "Heer" as [hiːɐ̯] and "hehr" as [heːɐ̯]. Google Translate's text-to-speech seems to support this.
So there seems to be a class of words where /e:/ gets pronounced /i:/ to my ears. Note that I cannot find anything online that supports that /e:/ ever turns into /i:/...
My (probably unreliable Chinese) ears hear [i:] in LEben, MEmel, strEben, etc. Dictionaries all agree on [e:], and no orthography description seems to mention
e pronounced as [i:] anywhere.
I am fairly sure that this isn't just a mishearing. Is this a very recent sound change? Hitler (sorry, no better example) seems not to use it, but that might be because he is Austrian?