D3 (and D4) lag issue and latency spikes

D3 lag issue / latency spikes.
Affects 64bit client and also D4, but not D3 32bit (although that has freezing/crashing periodically issues)

Basically, any time I am in game, I get constant stutter-like lag where animations or even walking will hit a delay or rubberband effect every 2-5 seconds. In D3 this is more of a delay where character moves but no attack animation happens, while in D4 this is more of a rubberband. Others in party describe my character as stop moving or attacking at all. At these times my latency goes from a 40-120 normal range to spiking to 300 or more.
Up until now, I had been using 32bit client workaround (with its own issues) but now that I have this problem in D4 also, I would like to get help resolving it.

Over time, I have tried all kinds of troubleshooting steps: reinstalling, updating OS and drivers, scanning for repair, messing with GPU settings, messing with network settings and hardware (I actually have had the issue through different modems and routers, and even had this issue on my old laptop), and all kinds of things I have found from google searching and searching the forums (such as sound channels being set to 16 and other tips).
Note: my girlfriend plays from the same home location, without this issue, on a Mac; and without this issue when playing D4 beta on windows bootcamp on her Mac.

Adding MTR, battle.net looking glass, and can add recent dxdiag when it allows me to reply (character limit on this post got in the way)

|------------------------------------------------------------------------------------------|

|                                      WinMTR statistics                                   |

|                       Host              -   %  | Sent | Recv | Best | Avrg | Wrst | Last |

|------------------------------------------------|------|------|------|------|------|------|

|                             SAC2V1A.lan -    0 |  642 |  642 |    0 |    0 |   15 |    0 |

|        142-254-146-221.inf.spectrum.com -    0 |  643 |  643 |    7 |   10 |   30 |    8 |

| lag-63.hcr02jfvlinbj.netops.charter.com -    0 |  642 |  642 |    7 |   14 |   97 |    8 |

|   lag-31.lsvmkyzo01r.netops.charter.com -    0 |  643 |  643 |    8 |   15 |   30 |   10 |

| lag-24.rcr01clmkohpe.netops.charter.com -    0 |  643 |  643 |   16 |   23 |  222 |   23 |

|lag-415.chctilwc00w-bcr00.netops.charter.com -    0 |  643 |  643 |   25 |   29 |  101 |   26 |

|lag-21.chcgildt87w-bcr00.netops.charter.com -    0 |  643 |  643 |   26 |   32 |  231 |   31 |

|    lag-401.pr2.chi10.netops.charter.com -    0 |  643 |  643 |   25 |   31 |   75 |   31 |

|                            24.30.201.81 -    0 |  643 |  643 |   26 |   33 |  104 |   26 |

|                           137.221.69.29 -   61 |  160 |   63 |  659 | 2633 | 4984 | 4954 |

|         et-0-0-3-br02-eqla1.as57976.net -    0 |  643 |  643 |   72 |   85 |  301 |  100 |

|                           137.221.68.87 -    0 |  643 |  643 |   72 |   75 |  114 |   73 |

|        lax-eqla1-ia-bons-02.as57976.net -    0 |  643 |  643 |   73 |   77 |   92 |   73 |

|                           24.105.30.129 -    0 |  643 |  643 |   72 |   76 |   91 |   77 |

|________________________________________________|______|______|______|______|______|______|

   WinMTR v0.92 GPL V2 by Appnor MSP - Fully Managed Hosting & Cloud Provider
PING:
PING 74.131.79.185 (74.131.79.185) 56(84) bytes of data.
64 bytes from 74.131.79.185: icmp_seq=1 ttl=52 time=31.6 ms
64 bytes from 74.131.79.185: icmp_seq=2 ttl=52 time=27.8 ms
64 bytes from 74.131.79.185: icmp_seq=3 ttl=52 time=27.1 ms
64 bytes from 74.131.79.185: icmp_seq=4 ttl=52 time=28.3 ms

--- 74.131.79.185 ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 2998ms
rtt min/avg/max/mdev = 27.160/28.750/31.652/1.732 ms


20/03/2023 20:56:35 UTC
--------------------

TRACEROUTE:
traceroute to 74.131.79.185 (74.131.79.185), 15 hops max, 60 byte packets
 1  24.105.63.82 (24.105.63.82)  10.376 ms  10.364 ms  10.363 ms
 2  * * *
 3  137.221.66.14 (137.221.66.14)  3.164 ms  3.179 ms  3.178 ms
 4  * * *
 5  137.221.69.28 (137.221.69.28)  3.167 ms  3.166 ms  3.166 ms
 6  lag-1061.pr2.chi10.netops.charter.com (24.30.201.80)  3.148 ms  8.410 ms  8.366 ms
 7  lag-111.chcgildt87w-bcr00.netops.charter.com (66.109.5.224)  8.396 ms  8.396 ms  8.394 ms
 8  lag-11.chctilwc00w-bcr00.netops.charter.com (66.109.6.21)  6.537 ms  6.661 ms  1.779 ms
 9  lag-1.rcr01clmkohpe.netops.charter.com (66.109.6.69)  11.717 ms  11.752 ms  12.042 ms
10  lag-1.lsvmkyzo01r.netops.charter.com (65.189.140.163)  23.049 ms  23.090 ms  23.251 ms
11  lag-1.hcr02jfvlinbj.netops.charter.com (24.33.107.115)  20.997 ms  21.010 ms  21.008 ms
12  tge7-1.jfvlinbj08m.swo.rr.com (74.128.6.14)  29.725 ms  29.940 ms  30.092 ms
13  cpe-74-131-79-185.kya.res.rr.com (74.131.79.185)  27.467 ms  27.901 ms  27.917 ms


20/03/2023 20:56:35 UTC
--------------------

MTR:
Start: Mon Mar 20 20:56:35 2023
HOST: ord1b-admin-looking-glass-back01             Loss%   Snt   Last   Avg  Best  Wrst StDev
  1.|-- 24.105.63.82                                  0.0%    10    1.2   1.4   1.0   2.6   0.0
  2.|-- ???                                          100.0    10    0.0   0.0   0.0   0.0   0.0
  3.|-- 137.221.66.14                                 0.0%    10    1.1   1.1   1.0   1.1   0.0
  4.|-- 137.221.69.78                                50.0%    10  10469 10331 10057 10566 197.6
  5.|-- 137.221.69.28                                 0.0%    10    1.9   1.7   1.5   2.0   0.0
  6.|-- lag-1061.pr2.chi10.netops.charter.com         0.0%    10    1.1   2.7   1.0  15.5   4.5
  7.|-- lag-111.chcgildt87w-bcr00.netops.charter.com  0.0%    10    1.8   6.5   1.6  48.7  14.8
  8.|-- lag-11.chctilwc00w-bcr00.netops.charter.com   0.0%    10    2.0   2.0   1.7   2.4   0.0
  9.|-- lag-1.rcr01clmkohpe.netops.charter.com        0.0%    10   11.6  11.7  11.5  12.3   0.0
 10.|-- lag-1.lsvmkyzo01r.netops.charter.com          0.0%    10   21.6  24.6  21.3  27.8   2.2
 11.|-- lag-1.hcr02jfvlinbj.netops.charter.com        0.0%    10   20.2  23.7  20.2  39.0   6.0
 12.|-- tge7-1.jfvlinbj08m.swo.rr.com                 0.0%    10   29.7  29.7  29.6  29.9   0.0
 13.|-- cpe-74-131-79-185.kya.res.rr.com              0.0%    10   27.6  30.6  27.3  34.7   2.8


20/03/2023 20:56:35 UTC
--------------------