N750 problem with DLNA Certified Samsung Series C

Good luck, I just want my router to not lock up every day. I can successfully dlna from a usb hdd to a tablet using mkv files from a n900 non central router just fine. Might be a mkv issue. Dlna should not transcode anything, just stream the raw file. The problem might be speed related and the stream falls on its face and quits. This would look like stuttering for about 1 or 2 seconds then die. I do my mkv playing over wifi to tablet