It seems like this is an issue very specific to me and I believe has been ongoing since I bought the game awhile back. For the longest time I thought no one wanted to talk to me because I would send out chats and others wouldn't respond. It was not until recently that that some friends of mine got the game and we soon discovered that they could read everything I sent out but I couldn't read/hear the messages they sent out.
Here is my steam profile:
http://steamcommunity.com/profiles/76561198088095151/