I've been using this wifi range extender for some time, but the connection has never delivered more than 70mbps. It's connected to a Linksys router via a FE cable. The main router provides 800+mbps wired and about 600mbps wifi on the 5ghz band. I've spent the day trying to troubleshoot the cause of the bottleneck and it keeps coming back to the extender itself. My Samsung tablet (that typically connects downstairs to the extender) gets 380mbps from the primary router when next to the primary router. To test, I've bypassed the ethernet to downstairs and connected it directly to the main router with a working FE cable and still get only 60mbps from the extender when standing next to it. I've tested with a laptop, tested the cables, the location, and no improvement.

Since I'm trying to increase bandwidth I've disabled the 2.4GHZ to force connection to 5ghz. I've tried to see if there's configuration issue, but I can't find one. I flashed the latest firmware. (One thing I noticed though is that the label says the hardware version is Ver. 3.8 but the web interface says the hw version is TL-WR902AC v3 00000001 ... do I trust the label or is it 3.0 HW version). I flashed the version for HW 3.8 and see no improvement.

Any suggestions or is this thing simply incapable of supporting more than 100mbps (advertized as 433mbps at 5ghz)

It's set to AP Ring/Ext/Client mode, on the same subnet at the main router.

Thanks