Empty response on Transaction Details [Sandbox credentials]

[idlikesometea]

I'm testing some transactions with sandbox credentials and they're working fine, but then I try to pull the transaction details im just getting this 

AuthorizeNetTD_Response Object
(
    [xml] => 
    [response] => 
)

On production with live credentials everything is working fine, any clue?  

[RichardH]

Please follow the instructions in the thread below to help us isolate this issue.

http://community.developer.authorize.net/t5/Integration-and-Testing/Response-returning-empty/m-p/525...

Richard