High error rate and massive drop in speed first thing in the morning

Lately I have been having issues with the internet speed dropping really low first thing in the morning.

I am on the 75mbps tier and I normally see 90-100 down and 5-7 up...

However first thing in the morning I was getting massive drop outs on my VOIP phone and huge delays on my work computer connected to a VPN...  when i tested i was seeing 3-4 up and 5-7 down...

each time a reboot it corrected this restoring normal function, but then first thing in the morning the next day it was back to 3-4 down and 5-7 up...  again a reboot corrected this

I figured that i had been running this router and modem for 3+ years, maybe it was time to upgrade...???  

I also decided to take a look at modem internal config page... (Zoom 5345)  Within minutes of a reset i was seeing several uncorrectable errors

Downstream was around 5.0 dBmV, SNR was about 35-40db

upstream power was about 45.5-48dBmV

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Here is where it all gets interesting... over th weekend I had disconnected the cable feed from the house and removed some unused splitters, one went to a peice of broken cable, the other had been capped off with a terminator...  other than that the only thing inline was a ground block...

in retrospect I should have been looking at this... 

especially since i have lived at the house since late 2008 and the cable line was there  when I moved in...  botht he drop and the in house line...

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BUT I decided to purchase a new modem... Motorola MB7420...  less than 18 hours after powering up this is what i see

Downstream Bonded Channels

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
1 Locked QAM256 4 399.0 5.1 39.2 15 0
2 Locked QAM256 5 405.0 4.9 39.0 12 0
3 Locked QAM256 6 411.0 4.8 39.1 9 0
4 Locked QAM256 7 417.0 5.1 39.3 8 0
5 Locked QAM256 8 423.0 4.9 39.2 1 0
6 Locked QAM256 9 435.0 5.1 39.4 0 0
7 Locked QAM256 10 441.0 4.9 39.3 7 0
8 Locked QAM256 11 447.0 4.8 39.3 1 0
9 Locked QAM256 12 453.0 5.0 39.4 1762 8814
10 Locked QAM256 13 459.0 5.1 39.5 769 873
11 Locked QAM256 14 465.0 5.1 39.5 0 0
12 Locked QAM256 15 471.0 5.1 37.2 0 0
13 Locked QAM256 16 477.0 5.4 38.0 0 0
14 Locked QAM256 17 483.0 5.4 39.6 0 0
15 Locked QAM256 18 489.0 5.5 39.5 2 0
16 Not Locked Unknown 0 495.0 0.0 0.0 1063 5651
Total 3649 15338

Upstream Bonded Channels

Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 6 5120 31.4 46.8
2 Locked ATDMA 5 5120 37.8 48.0
3 Locked ATDMA 7 5120 25.0 46.5
4 Locked ATDMA 8 5120 18.6 47.3