Salaam ‘Alaykum.If you pray behind someone and you are not sure whether he correctly pronounced the sharp haa (حاء) in Sami’-Allaahu liman hamidah, is the prayer valid? And is it correct to go up to that person and inquire and is it also valid to continue to pray behind him while having this doubt? May Allaah reward you with good.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

The prayer is valid, because saying Sami’a Allahu Liman Hamidah when raising from the Rukoo’ is a recommended act and not an obligation according to the opinion of the majority of the scholars. Therefore, if one leaves it out completely, then the prayer would still be valid.

You are not Islamically required to ask the Imam whether or not he pronounced the letter Haa’ (حاء) correctly, as in principle he pronounces it correctly.

Being extreme about this matter is an exaggeration in religion. You should beware of making him become doubtful and have whispers, because it would be a great trial for him.

Allah knows best.