proper pronunciation of arabic diacritics

[Aqdas]

many of us from the subcontinent will say salle 'ala and the arabs will say salli 'ala.

we will say alhamdo; they will pronounce it correctly as alhamdu.

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1. are we saying it incorrectly?
2. if so, how serious a mistake is it: 2a) in salah 2b) out of salah?

[sherkhan]

Originally Posted by Aqdas

1. are we saying it incorrectly?

Yes. The subcontinent pronounciation for kasrah/dammah is wrong.

Originally Posted by Aqdas

2. if so, how serious a mistake is it: 2a) in salah 2b) out of salah?

I'm given to understand that pronouncing 'o' for 'i' can even change meaning of certain words (in which case whether in or out of salah, the mistake becomes very serious).

I heard in a tajweed class that alhamdo (instead of alhamdu) has pejorative connotations. Since I haven't read or heard this explanation elsewhere, I don't know if this true. Arabic experts can confirm/refute the above.