While searching for possible work arounds regarding this issue I found the following suggestion;
dial your 10 digit google voice number,press the number 2,dial the 10 digit number you want to call then press #.I tried it and while it took me several attempts to get to the prompt to tell me how to place a call it did work. The site where I found this says the issue is google voice transitioning from XMPP protocol features and moving everyone to GV-SIP protocol.