Internet dropping at random intervals

[spartan7]

Our internet is dropping randomly for a few sec. Here is the image I see on the dashboard graph.

have no idea why this is happening, but sometimes the interruption is so small it does not affect voip calls.

[cmb]

That's what happens when the counter loops, it's not actually a drop in traffic at all. It's a 32 bit counter on 32 bit OS so it wraps frequently at decent throughput.