I got the same problem with an SG3216v2 and an SG3424v1.
Ican get in the 3424 from the webpage, but the is no response from the console
I forgot the password from the 3216, can see the webpage, but there is also no response from the console.
I tried with hyperterminal, putty and teraterm.
I used the usb-Adapter before the is no fault.
... strange ....