Who creates the Phoneme files?

[urbexuk]

I use HERE maps and a lot of names of streets are spoken incorrect. I have contacted HERE and they said they do not provide phonetic files to iGO so who makes and decides the phoneme files for them?

also, is there a manual way to change the way street names are pronounced?
example
Town of Dalry in Scotland is spoken as Dal Rie on igo, however the proper way to say it is Dal Rye and Milingavie near Glasgow is said as Milin Gavie yet its proper pronounced Mill Guy.

I use WINCE device not an android one.