I have the same issue with my 5 new E9+, that i have recived yesterday. I have 2 E9+ recived in December and they work fine. But with this 5 i have became crazy. Their default ip is 192.168.80.140, I configurate my router's ip as 192.168.80.1, using network scanner i see that when i power on E9 it is visible in network for one minute and then red light becomes to blink and e9 lost. the same issue with all 5 e9. I cant understand what hapens.
While the sticker always says the IP is 80.140 the truth is that they almost never are matched to that setting. The 1500 I purchased were all DHCP
Now everything is good. They all came with DHCP disabled. Using their soft EbiteMinerMini found them on 192.168.120.--- network, only when connect laptop via cable to my router. EbiteMinerMini DOESN'T WORK with WIFI connection, ONLY CABLE. Thank you.
As for IP 80.140. I saw that 192.168.80.140 appeared in the network for 1 minute and then lost. So I think that this is some kind of bootloader using for factory settings or flashing firmware or something else.