Something may be blocking/dropping packets along the routes in play. Both of you may need to check a few things out. Run the latency test at testmy.net: https://testmy.net/latency Click the icon with the eye on it to run all the tests back to back. Watch what the line graphs are doing. If they are continually spiking really high and you keep getting high deviation numbers, then you may have a latency/jitter problem for your ISP to investigate. Each of the individual test graphs will note the address it tested, so you can look closer at that particular route (run traces and such)... sometimes a certain exchange point is a common denominator they can look at. There is another batch ping test you can run at dslreports.com for extra comparison as well: http://www.dslreports.com/tools/pingtest Yes, I know many of the test locations are a long way away and the core latency will be too high for the game... what you are testing for is the consistency of the latency. If there is too much jitter or packet loss, the game will boot you. Also need to make sure your local network is in line with Bungie's network guide: https://www.bungie.net/en/Support/Troubleshoot?oid=12915