tl;dr version: Newer Tomato Shibby N5x firmwares can cause dramatically higher power consumption on mobile devices than AC6x firmwares. This can happen just by being connected to the router and idling. I spent a few hours figuring this out yesterday, perhaps this is already a known issue but I thought I would post it in the event it could be of use to someone. (router) Asus RT-N66U 2ghz/5ghz wifi: both using "n only", wpa2 personal, aes (phone) Nexus 5 running stock android 4.4.2 with no background programs running. Wireless chip is a Broadcom BCM4339 tomato-K26USB-1.28.RT-N5x-MIPSR2-105-AIO-64K.trx Had been running with this firmware for months with no problem. tomato-K26USB-1.28.RT-N5x-MIPSR2-115-AIO-64K.trx Upgraded to this firmware (did nvram clear at installation) and mobile battery use shot up. The total power consumption for the device sitting on a table with the screen off jumped from 0.8%/hour to 5.5%/hour after installing this firmware. tomato-RT-N66U_RT-AC6x--115-AIO-64K.trx Switched to this firmware and battery use went back down to 0.8%/hour. (things I tried that no effect) Changing between the 2ghz and 5ghz access points. Clearing all of the saved access points from the phone, putting phone in airplane mode, rebooting phone, changing the phone's wifi scanning settings. Creating new access point names/passwords on the router, changing channels, clearing nvram and manually entering settings, static vs random dhcp assignment. Also while this was happening the phone was not transmitting data (I disabled syncing for the test) it was merely connected to the AP. The device shows no unusual wakelocks, there is no program in the background waking the device up. The only service that showed higher than normal power consumption was the Android "WiFi" process. (what it could have been) I had read that some were able to solve similar problems by messing with "Beacon Interval" or "DTIM Interval". Possibly due to a beacon timing issue preventing the phone from from entering deep sleep in-between intervals. I did not touch any of these settings and left them on default. I had also read that the AC6x firmwares used a newer driver for the radios so perhaps that was what made the difference. I still don't know for sure if this was a Tomato bug, a Broadcom bug, or an Android bug. In any event everything seems to be working now.