Sky mobile Ireland cannot hear callers

[cmie]

I moved from Vodafone mobile to sky mobile last October. Since then, when contacts who I speak with on a regular basis call me we cannot hear each other. I have to hang up and call them back and then have no issues.

From what I can make out if my contacts are Vodafone users, there is no issue but if they are not, we cannot hear each other when they ring me. 
I have the issue with callers using Virgin mobile, gomo, and Eir mobile.

i never had this issue with my Vodafone account.

has anyone else experienced this?

[JDeeIE]

Tele2 call handling outside of Vodafone calls on the same network? 

[cmie]

I'm not sure what that means. Are you asking me to check something? Thank you

[JDeeIE]

No it's a technical setting, Tele2 seem to handle roaming for Sky Ire. 

My call quality wasn't the best, assume traffic maybe routed outside Ire. 

if you go to sim settings (sim applications iPhone) make sure you aren't using ">Partners Settings" assuming that's Tele2 

the > should be on  >Automatic