I am guessing that you pronounce bird and curd the same but to me they are different and it may be the Asian pronunciation is similar to mines and with an Asian accent it is mis-heard as Britch.
What I was getting at is that you and your pal may pronounce their name to sound like burch whereas I and possibly Asians sound the 'I" and roll it as JOKO said. As you are maybe not used to that, you and your pal hear it as 'britch'-is that clearer?
If your friend has not already done so, I have found that without my name in the telephone directory I get far less bother. So long as everyone who needs it has the number, you do not need to be ex-directory but just tell them so in case they forget it. On the occasions I do get bothered, I just put down the phone on the table and walk away.