TMobile Internet and Buffering

If you are seeing excessive buffering it is probably due to low bandwidth. If the cellular source is busy or there is some problem that restricts bandwidth and service delivery buffering is going to happen. I suggest you run a speed test with say the Speedtest.net application and confirm the download and upload speeds you are experiencing. 

If you have one of the newer gateways from T-Mobile you will not be able to determine if the statistics are clean for transmit and receive other than look at what the client reports about the network connection. It might be related to errors or drops but more than likely it is due to tower congestion. A speed test can provide clues as to bandwidth to the client and latency as reported by the application for ping latency and also jitter. If latency is high and bandwidth is low more than likely there is throttling of the traffic due to load. T-Mobile might be doing work on the cell tower so that could be another avenue to investigate. My guess is heavy user load and bandwidth throttling.