[Solved] Getting bad bufferbloat, SQM only makes it WORSE - reverted to stock firmware

He should be able to gain access to the modem gui if it's in a diffrent subnet...
See: [SOLVED] How to access the modem (which is in bridge mode)? - #11 by angelos
It's quite easy and you can set it over Luci... i have a similar setup with a modem working in full bridge mode, but i dont think that will make a difference.