I heard from a friend years ago that one of the Rebbes from Gur (possibly the S'fas Emes) wrote a book describing the proper pronunciation of Hebrew letters and words. I am not able to find any trace ...
My cousin, a Lubavitcher, says both zecher and zeicher (that is, both זֶכֶר with a segol and זֵכֶר with a tzeire) in "Ashrei". I noticed this when I visited him a good few years ago, and assumed it ...
I prayed using a Siddur Tehillat Hashem the other day, and I noticed that many more shvas were marked with an asterisk above, indicating that they should be vocalized, than I'd expect. In particular, ...