Anyone pronouncing the Choulom as an “oy” sound unless the Choulom is followed by a “Yud” is ignorant of the rules of correct Hebrew pronunciation. There are only 2 authentic & hence correct pronunciations:- 1) “Oh” as in Go. 2) “Ow” as in How or House.
Anyone who is ignorant of this rule of reading Hebrew should urgently read Rav Hamburger’s learned & intricate details & explanation of this fact; Urgently:- so by next Kerias Shema, you will at least fulfill a Toroh obligation correctly.