Frequent packet loss and intermittent lags - looking for answers

Been at this house for 9 years with consistent service, but some terrible packet loss has cropped up in the last month. Frequent lags in any video game (every 2-3 minutes) and occasionally will briefly cut out on video calls while working. (tested hard wired direct to modem, issue persists on 3 different PCs)

I've had a technician visit twice in the last week. The first tech claimed there was no issue with the signal coming to my home, but poor signal on the cable from the box on the outer wall to the splitter inside. He replaced the splitter with a MoCA filter (I don't have cable TV and have never needed one here before), told me my signal looked good and left. Issues did not change so I scheduled a follow-up visit noting the issue had not been resolved. Because I rescheduled, they sent another tech (may have been a supervisor) who said the MoCA filter made no difference, but did not see signal issues anywhere. Strong signal all the way up to the modem. Because of this he told me there was nothing they could do, and to try replacing my modem.

I replaced my 2 year old Netgear CM2000 with a CM3000 today, running through Xfinity's internet trouble shooting guide both before and after the purchase and set-up of the new modem. Unfortunately the new modem has made no difference. There has got to be noise ingress somewhere. I live in a group of townhomes with a lot of units sharing pedestals, it feels difficult to pinpoint where there is noise or getting Xfinity to take a serious look at where it is coming from. The issue being intermittent makes it difficult to test, open to suggestions! I am willing to work with Xfinity and pay to replace wiring in my home if necessary, but need them to meet me halfway and stop dismissing the issues with my service.

Some errors I get from the Event log on both the old and new modem:

Started Unicast Maintenance Ranging - No Response received - T3 time-out

SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing

RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW

Based on the Xfinity trouble-shooting guide, some of the ranging errors can be normal but I don't know how often is normal. Viewing the export from the modem, the signal looks good and matches the specs Xfinity provides in the guide. No correctables/uncorrectables that I see, but not sure how to catch that "in the act" so to speak. Thank you in advance for any help!

Netgear CM3000

Downstream Bonded Channels

Channel	Lock Status	Modulation	Channel ID	Frequency	Power	SNR	Correctables	Uncorrectables
1	Locked	QAM256	4	393000000 Hz	1.5 dBmV	41.0 dB	0	0
2	Locked	QAM256	1	375000000 Hz	2.1 dBmV	41.2 dB	0	0
3	Locked	QAM256	2	381000000 Hz	2.5 dBmV	41.3 dB	0	0
4	Locked	QAM256	3	387000000 Hz	2.1 dBmV	41.2 dB	0	0
5	Locked	QAM256	5	399000000 Hz	1.0 dBmV	40.8 dB	0	0
6	Locked	QAM256	6	405000000 Hz	0.3 dBmV	40.5 dB	0	0
7	Locked	QAM256	7	411000000 Hz	0.5 dBmV	40.5 dB	0	0
8	Locked	QAM256	8	417000000 Hz	0.1 dBmV	40.3 dB	0	0
9	Locked	QAM256	9	423000000 Hz	0.1 dBmV	40.3 dB	0	0
10	Locked	QAM256	10	435000000 Hz	0.8 dBmV	40.6 dB	0	0
11	Locked	QAM256	11	441000000 Hz	0.6 dBmV	40.6 dB	0	0
12	Locked	QAM256	12	453000000 Hz	1.3 dBmV	40.9 dB	0	0
13	Locked	QAM256	13	459000000 Hz	1.2 dBmV	40.7 dB	0	0
14	Locked	QAM256	14	465000000 Hz	1.4 dBmV	40.7 dB	0	0
15	Locked	QAM256	15	471000000 Hz	1.3 dBmV	40.7 dB	0	0
16	Locked	QAM256	16	477000000 Hz	1.5 dBmV	40.8 dB	0	0
17	Locked	QAM256	17	483000000 Hz	2.0 dBmV	40.9 dB	0	0
18	Locked	QAM256	18	489000000 Hz	2.1 dBmV	40.9 dB	0	0
19	Locked	QAM256	19	495000000 Hz	2.1 dBmV	41.0 dB	0	0
20	Locked	QAM256	20	501000000 Hz	1.7 dBmV	40.9 dB	0	0
21	Locked	QAM256	21	507000000 Hz	2.0 dBmV	41.0 dB	0	0
22	Locked	QAM256	22	513000000 Hz	2.4 dBmV	41.2 dB	0	0
23	Locked	QAM256	23	519000000 Hz	2.3 dBmV	41.1 dB	0	0
24	Locked	QAM256	24	525000000 Hz	2.3 dBmV	41.1 dB	0	0
25	Locked	QAM256	25	531000000 Hz	1.8 dBmV	41.0 dB	0	0
26	Locked	QAM256	26	537000000 Hz	3.0 dBmV	41.3 dB	0	0
27	Locked	QAM256	27	543000000 Hz	3.1 dBmV	41.3 dB	0	0
28	Locked	QAM256	28	549000000 Hz	2.4 dBmV	41.1 dB	0	0
29	Locked	QAM256	29	555000000 Hz	2.1 dBmV	41.0 dB	0	0
30	Locked	QAM256	30	561000000 Hz	3.1 dBmV	41.3 dB	0	0
31	Locked	QAM256	31	567000000 Hz	3.2 dBmV	41.4 dB	0	0
32	Locked	QAM256	32	573000000 Hz	2.8 dBmV	41.3 dB	0	0

Upstream Bonded Channels

Channel	Lock Status	US Channel Type	Channel ID	Symbol Rate	Frequency	Power
1	Locked	ATDMA	6	2560 Ksym/sec	10400000 Hz	39.0 dBmV
2	Locked	ATDMA	2	5120 Ksym/sec	22800000 Hz	36.0 dBmV
3	Locked	ATDMA	3	5120 Ksym/sec	29200000 Hz	36.0 dBmV
4	Locked	ATDMA	4	5120 Ksym/sec	35600000 Hz	36.0 dBmV
5	Locked	ATDMA	5	2560 Ksym/sec	40400000 Hz	33.5 dBmV
6	Locked	ATDMA	1	5120 Ksym/sec	16400000 Hz	37.0 dBmV
7	Not Locked	Unknown	0	0	0	0.0 dBmV
8	Not Locked	Unknown	0	0	0	0.0 dBmV

Downstream OFDM Channels

Channel	Lock Status	Profile ID	Channel ID	Frequency	Power	SNR / MER	Active Subcarrier Number Range	Unerrored Codewords	Correctable Codewords	Uncorrectable Codewords
1	Locked	0 ,1 ,2 ,3	193	690000000 Hz	1.38 dBmV	40.6 dB	1108 ~ 2987	445484276	414412226	0
2	Not Locked	0	0	0 Hz	0 dBmV	0 dB	0 ~ 4095	0	0	0

Upstream OFDMA Channels

Channel	Lock Status	Modulation / Profile ID	Channel ID	Frequency	Power
1	Not Locked	0	0	0 Hz	0 dBmV
2	Not Locked	0	0	0 Hz	0 dBmV

Event Log from setup of new CM3000 today

Time	Priority	Description
Tue Jan 21 19:12:46 2025	(Critical (3))	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:21:51 2025	(Warning (5))	Dynamic Range Window violation
Tue Jan 21 12:21:51 2025	(Warning (5))	RNG-RSP CCAP Commanded Power Exceeds Value Corresponding to the Top of the DRW;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:21:46 2025	(Critical (3))	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:21:30 2025	(Notice (6))	DS profile assignment change. DS Chan ID: 32; Previous Profile: ; New Profile: 1 2 3.;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:21:25 2025	(Notice (6))	TLV-11 - unrecognized OID;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Notice (6))	Honoring MDD; IP provisioning mode = IPv6
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:20:13 2025	(Critical (3))	Resetting the cable modem due to docsDevResetNow
Tue Jan 21 12:19:33 2025	(Critical (3))	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:15:53 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:14:08 2025	(Critical (3))	Resetting the cable modem due to docsDevResetNow
Tue Jan 21 12:14:06 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 12:03:12 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:55:17 2025	(Critical (3))	Started Unicast Maintenance Ranging - No Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:50:31 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:50:09 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:47:56 2025	(Critical (3))	Resetting the cable modem due to docsDevResetNow
Tue Jan 21 11:45:11 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:44:29 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:41:30 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:40:59 2025	(Critical (3))	No Ranging Response received - T3 time-out;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Tue Jan 21 11:40:07 2025	(Critical (3))	SYNC Timing Synchronization failure - Loss of Sync;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;
Time Not Established	(Critical (3))	SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing;;CM-MAC=(Redacted);CMTS-MAC=(Redacted);CM-QOS=1.1;CM-VER=3.1;

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Frequent packet loss and intermittent lags - looking for answers

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