And we are seeing A lot of problems with the 2.4 systems also. They tend to lock up for 4 seconds after signal loss. The loss of signal can be A low battery or just the angle of the antenna of the TX and plane. Now A third and even fourth RX is being offered for the systems for this reason. Nothing is fool proof.
Ken said it all, just send in your crashed gear and have it checked out, it's worth the price to have it done just for the piece of mind.