Good Afternoon James! Wifi is a bit of a fickle beast especially when attempting to compare devices and even more so when attempting to compare different devices behaving in different environments! My tablet routinely averages around 35-45 megabits per second in my home and in my office running over Wireless 2.4ghz N. I personally still prefer 5ghz AC (at least when booted into windows) so I use a small USB dongle that cost me around $10 and it barely protrudes from the unit or adds any weight, so just something to consider! Things that MAY be effecting your speed though.
Are you utilizing bluetooth devices at the same time (keyboards, headphones, mouse, etc. Anything bluetooth connected to the device). The Hi12 like many budget machines has shared radio resources for BT andWifi. So basically having accessories hooked up via BlueTooth is going to be detrimental to your WiFi (and vice versa). If you AREN’T using bluetooth you might try turning bluetooth off and seeing if that has any impact on your WiFi performance!
Every unit is different but it sounds like you are seeing sub-par performance in more then one environment so it sounds like it is the device rather then external limitations. Outside of my concern about bluetooth devices it may just be that your device has poor shielding or other quality control type issues that could ave resulted in reduced wi-fi performance but again, easily rectifiable (at least in windows) with a cheap wifi dongle.
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