Model : TD-W8961ND

Hardware Version : V3

Firmware Version : Build 140305 Rel.04531

ISP : Vivo Internet Fixa

I'm having disconnection problems for quite long now with this modem, however, the disconnection period is oddly randomic, as sometimes it tends to be stable, and others, disconnection each 10 seconds to 1 minute. I do have another wireless router, but I've tried disabling the wi-fi feature but the problem still persists. Checking the logs, I see this error constantly repeating itself as well:

5/17/2016 13:23:50> netMakeChannDial: err=-3000 rn_p=804cfe38
5/17/2016 13:23:51> Last errorlog repeat 2 Times
5/17/2016 13:23:52> netMakeChannDial: err=-3000 rn_p=804cfe38
5/17/2016 13:23:52> Last errorlog repeat 2 Times
5/17/2016 13:23:54> netMakeChannDial: err=-3000 rn_p=804cfe38
5/17/2016 13:23:56> Last errorlog repeat 8 Times
5/17/2016 13:23:57> netMakeChannDial: err=-3000 rn_p=804cfe38
5/17/2016 13:23:58> Last errorlog repeat 22 Times
5/17/2016 13:24:3> netMakeChannDial: err=-3000 rn_p=804cfe38
5/17/2016 13:27:6> Last errorlog repeat 96 Times

I've also tried checking with my provider, who says the external connection is normal. Could this be an internal problem?