First time poster here. I recently purchased the HTC M9 and I seem to be having issues with group MMS. I also had the same issue with my HTC M8 as well, so perhaps it is a HTC problem? Although it only ever seems to be from iPhones that I am having this issue but when I am in a group chat with friends, I get all of the android messages but only about 80% of the iPhone messages. Sometimes, I get the iPhones messages hours or days later that are completely out of place.
I notice that gaps are missing in conversations that I don't follow to find out I didn't receive all of the messages in the group. My friend with his Samsung doesn't seem to have this problem, who is in the same chat. I am currently with T-Mobile and don't want to start messing with the APN settings unless I need to.
Has anyone else had this problem? I have never owned an iPhone, so it isn't the iMessage setting on the iPhone side preventing messages from getting to me. Thanks for all the assistance in the matter!