I've recently bought used Cisco SPA112, however I cannot configure it. I have resetted it to factory settings with reset button (it worked well), connected to my router's LAN switching port and tried to login to Web interface as "admin" - SPA112 got all the config using DHCP.
When I open "Network Setup" menu, the interface hangs and I cannot do anything. The ATA answers to ping packets with 1 ms or less latency, however trying to open Web panel in a new tab fails - no error shows up, the webpage is trying to load without any effect for an indefinite time (I have it now hanging for about 10 minutes, nothing's happening). After rebooting the ATA using button, the panel shows again and still hangs when trying to access the "Network setup" menu.
Even though the Web panel is inaccessible, IVR menu is responding after setting modem's dial tone detection off (as there is no dial tone or it's too silent). I've tried switching connection type to static IP (IVR option 101 set to 1), however I couldn't set static IP address nor network mask (got "invalid option" response for both 111# and 121#). I've checked 100# for checked option, sometimes the IVR system hasn't answered anything, just silence, then back to main menu, another time it announced the option set as it should. Doing nmap scan shows that port 80 is still open with running HTTP service, even though it's frozen.
A few reboots and factory resets later I've even tried firmware upgrade as the firmware version on the device is 1.3.1 (003) and current is 1.4.1 SR5, hoping that it's going to fix all the issues. After connecting the ATA directly to my server (being a DHCP server for my network, to let it get the IP and not to lose connection again). I've downloaded the BIN file from Cisco website and tried to load it using the Web panel (surprisingly, the "Firmware upgrade" submenu opened without crashing the panel). However, when the upgrade procedure started, it got stuck on 98% with no response from Web panel again for about half an hour. Putting a modem off-hook made its telephone port LED flash, entering IVR menu was successful as well, pings were still reaching the device, however ATA was still stuck in upgrade mode - I had to factory reset it again (yes, it was an incredibly dangerous, although I found it necessary to go anywhere further). Local logging has been enabled in debug mode for both kernel and system, but enabling Syslog hung the panel again.
Is there any way to fix it without throwing the ATA away and buying a new one?
Thank you in advice for your answers.