is above parameter for your neighbor? holy crap, the margin is super low!!
ok, seems that the attenuation is very very very very high, that answers why u get a lot of dc.

but if ur neighbour didnt get dc even he gets high attenuation, i suspect your cable is faulty. modem is not the case here, seems u already changed it 3 times.

fyi, i aslo get dc-ed every 5-10 minutes a couple of months ago. then i ask the tm technician (not tmnet one) to check my cable. he came to my house, tracing the cable from the box (as shown in your pics) to my house. he rewired the cable (not rewired actually, just reconnect the wire from my house to the ones at the box using a connector (black in colour)). after that, no more dc.