CM3000 Comcast Business Slow Upload

Question

Using the Comcast provided modem I get &gt; 300 Mbps upload.&nbsp; Changing to the CM3000 I get 30.&nbsp;I've spent hours with Comcast tech support and had multiple technicians out.&nbsp;Thoughts?&nbsp;Cable DiagnosticStatus: GoodAction:Your setup looks fine. If you can't access the internet, make sure you properly activated the modem. If modem has been activated and you still can't access the internet, contact your service provider for troubleshooting help.If you can access the internet but has other internet issue, the Netgear Cable Knowledge Base can provide additional troubleshooting info.CM Status: GoodDownstream Status: Good&nbsp; &nbsp; Downstream Power Level: Good&nbsp; &nbsp; Downstream SNR Level: GoodUpstream Status: Good&nbsp; &nbsp; Upstream Power Level: GoodCurrent Time: Wed Jun 18 10:14:04 2025Startup ProcedureAcquire Downstream Channel: 495000000 Hz &nbsp;LockedConnectivity State: &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;OK &nbsp; &nbsp; &nbsp; OperationalBoot State: &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp;OK &nbsp; &nbsp; &nbsp; OperationalSecurity: &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; Enabled &nbsp; BPI+IP Provisioning Mode: &nbsp; &nbsp; &nbsp; Honor MDD &nbsp; IPv6 onlyDownstream Bonded ChannelsChannel LockedStatus Modulation ChannelID &nbsp;Frequency &nbsp; &nbsp; Power &nbsp; &nbsp;SNR &nbsp; Correctables Uncorrectables &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 12 &nbsp; &nbsp; 495000000 Hz &nbsp; &nbsp; 4.5 &nbsp; &nbsp; 44.4 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 2 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;1 &nbsp; &nbsp; 429000000 Hz &nbsp; &nbsp; 5.4 &nbsp; &nbsp; 45 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 3 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;2 &nbsp; &nbsp; 435000000 Hz &nbsp; &nbsp; 5.4 &nbsp; &nbsp; 45 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 4 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;3 &nbsp; &nbsp; 441000000 Hz &nbsp; &nbsp; 5.2 &nbsp; &nbsp; 44.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 5 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;4 &nbsp; &nbsp; 447000000 Hz &nbsp; &nbsp; 5.2 &nbsp; &nbsp; 44.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 6 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;5 &nbsp; &nbsp; 453000000 Hz &nbsp; &nbsp; 5.2 &nbsp; &nbsp; 44.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 7 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;6 &nbsp; &nbsp; 459000000 Hz &nbsp; &nbsp; 5 &nbsp; &nbsp; 44.7 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 8 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;7 &nbsp; &nbsp; 465000000 Hz &nbsp; &nbsp; 4.9 &nbsp; &nbsp; 44.6 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 9 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;8 &nbsp; &nbsp; 471000000 Hz &nbsp; &nbsp; 4.8 &nbsp; &nbsp; 44.5 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;10 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; &nbsp;9 &nbsp; &nbsp; 477000000 Hz &nbsp; &nbsp; 4.8 &nbsp; &nbsp; 44.5 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;11 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 10 &nbsp; &nbsp; 483000000 Hz &nbsp; &nbsp; 4.6 &nbsp; &nbsp; 44.4 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;12 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 11 &nbsp; &nbsp; 489000000 Hz &nbsp; &nbsp; 4.6 &nbsp; &nbsp; 44.4 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;13 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 13 &nbsp; &nbsp; 501000000 Hz &nbsp; &nbsp; 4.5 &nbsp; &nbsp; 44.3 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;14 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 14 &nbsp; &nbsp; 507000000 Hz &nbsp; &nbsp; 4.4 &nbsp; &nbsp; 44.3 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;15 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 15 &nbsp; &nbsp; 513000000 Hz &nbsp; &nbsp; 4.2 &nbsp; &nbsp; 44.1 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;16 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 16 &nbsp; &nbsp; 519000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 44.1 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;17 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 17 &nbsp; &nbsp; 525000000 Hz &nbsp; &nbsp; 4.2 &nbsp; &nbsp; 44.1 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;18 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 18 &nbsp; &nbsp; 531000000 Hz &nbsp; &nbsp; 4.3 &nbsp; &nbsp; 44.2 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;19 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 19 &nbsp; &nbsp; 537000000 Hz &nbsp; &nbsp; 4 &nbsp; &nbsp; 44 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;20 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 20 &nbsp; &nbsp; 543000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 44 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;21 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 21 &nbsp; &nbsp; 549000000 Hz &nbsp; &nbsp; 4 &nbsp; &nbsp; 43.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;22 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 22 &nbsp; &nbsp; 555000000 Hz &nbsp; &nbsp; 4 &nbsp; &nbsp; 43.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;23 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 23 &nbsp; &nbsp; 561000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 43.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;24 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 24 &nbsp; &nbsp; 567000000 Hz &nbsp; &nbsp; 4 &nbsp; &nbsp; 43.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;25 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 25 &nbsp; &nbsp; 573000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 43.9 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;26 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 26 &nbsp; &nbsp; 579000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 43.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;27 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 27 &nbsp; &nbsp; 585000000 Hz &nbsp; &nbsp; 3.9 &nbsp; &nbsp; 43.7 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;28 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 28 &nbsp; &nbsp; 591000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 43.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;29 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 29 &nbsp; &nbsp; 597000000 Hz &nbsp; &nbsp; 4.1 &nbsp; &nbsp; 43.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;30 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 30 &nbsp; &nbsp; 603000000 Hz &nbsp; &nbsp; 3.9 &nbsp; &nbsp; 43.7 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;31 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 31 &nbsp; &nbsp; 609000000 Hz &nbsp; &nbsp; 4 &nbsp; &nbsp; 43.8 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp;32 &nbsp; &nbsp; Locked &nbsp; &nbsp; QAM256 &nbsp; &nbsp; 32 &nbsp; &nbsp; 615000000 Hz &nbsp; &nbsp; 3.9 &nbsp; &nbsp; 43.7 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0Upstream Bonded ChannelsChannel &nbsp; LockedStatus &nbsp;ChannelType ChannelID &nbsp; SymbolRate &nbsp; &nbsp; &nbsp; &nbsp;Frequency &nbsp; &nbsp; &nbsp; Power &nbsp; &nbsp;&nbsp;&nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp; &nbsp; Locked &nbsp; &nbsp; &nbsp; ATDMA &nbsp; &nbsp; 18 &nbsp; &nbsp; &nbsp; 5120 Ksym/sec &nbsp; &nbsp; &nbsp; 22800000 Hz &nbsp; &nbsp; &nbsp; 38.3 dBmV&nbsp; &nbsp; &nbsp; 2 &nbsp; &nbsp; &nbsp; Locked &nbsp; &nbsp; &nbsp; ATDMA &nbsp; &nbsp; 19 &nbsp; &nbsp; &nbsp; 5120 Ksym/sec &nbsp; &nbsp; &nbsp; 29200000 Hz &nbsp; &nbsp; &nbsp; 39.3 dBmV&nbsp; &nbsp; &nbsp; 3 &nbsp; &nbsp; &nbsp; Locked &nbsp; &nbsp; &nbsp; ATDMA &nbsp; &nbsp; 20 &nbsp; &nbsp; &nbsp; 5120 Ksym/sec &nbsp; &nbsp; &nbsp; 35600000 Hz &nbsp; &nbsp; &nbsp; 40.3 dBmV&nbsp; &nbsp; &nbsp; 4 &nbsp; &nbsp; &nbsp; Locked &nbsp; &nbsp; &nbsp; ATDMA &nbsp; &nbsp; 17 &nbsp; &nbsp; &nbsp; 5120 Ksym/sec &nbsp; &nbsp; &nbsp; 16400000 Hz &nbsp; &nbsp; &nbsp; 37.5 dBmV&nbsp; &nbsp; &nbsp; 5 &nbsp; &nbsp; &nbsp; Not Locked &nbsp; &nbsp; &nbsp; Unknown &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0.0&nbsp; &nbsp; &nbsp; 6 &nbsp; &nbsp; &nbsp; Not Locked &nbsp; &nbsp; &nbsp; Unknown &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0.0&nbsp; &nbsp; &nbsp; 7 &nbsp; &nbsp; &nbsp; Not Locked &nbsp; &nbsp; &nbsp; Unknown &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0.0&nbsp; &nbsp; &nbsp; 8 &nbsp; &nbsp; &nbsp; Not Locked &nbsp; &nbsp; &nbsp; Unknown &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp; 0.0Downstream OFDM ChannelsChannel &nbsp; LockedStatus &nbsp;ProfileID &nbsp;ChannelID &nbsp; &nbsp;Frequency &nbsp; &nbsp; &nbsp; Power &nbsp; &nbsp; &nbsp; SNR/MER &nbsp; &nbsp;ActiveSubcarrier &nbsp; &nbsp;Unerror &nbsp; &nbsp;Correctable &nbsp; Uncorrectable&nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp; Locked &nbsp; &nbsp; 0 ,1 ,2 ,3 &nbsp; &nbsp; 193 &nbsp; &nbsp; 957000000 Hz &nbsp; &nbsp; 1.58 dBmV &nbsp; &nbsp; 41.4 dB &nbsp; &nbsp; 148 ~ 3947 &nbsp; &nbsp; 6699720 &nbsp; &nbsp; 5862969 &nbsp; &nbsp; 0&nbsp; &nbsp; &nbsp; 2 &nbsp; &nbsp; Not Locked &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; 0 Hz &nbsp; &nbsp; 0 dBmV &nbsp; &nbsp; 0 dB &nbsp; &nbsp; 0 ~ 4095 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0 &nbsp; &nbsp; 0Upstream OFDMA ChannelsChannel &nbsp; LockedStatus &nbsp; &nbsp;ProfileID &nbsp; &nbsp;ChannelID &nbsp; &nbsp;Frequency &nbsp; &nbsp; &nbsp; Power&nbsp; &nbsp; &nbsp; 1 &nbsp; &nbsp; Locked &nbsp; &nbsp; 12 ,13 &nbsp; &nbsp; 43 &nbsp; &nbsp; 36200000 Hz &nbsp; &nbsp; 35.5 dBmV&nbsp; &nbsp; &nbsp; 2 &nbsp; &nbsp; Not Locked &nbsp; &nbsp; 0 &nbsp; &nbsp; &nbsp;0 &nbsp; &nbsp; 0 Hz &nbsp; &nbsp; 0 dBmV

Kitsap · Answer

For Comcast Business accounts, there is a chance the CM3000 has not been certified for connection to the Enhanced Speed Network.

Make a Technical Support post over on the Reddit Comcast_Xfinity forum and they should be able to give you an answer. https://www.reddit.com/r/Comcast_Xfinity/

FURRYe38 · Answer

Is this speed seen with a ethernet connected PC connected directly behind the CM modem? No router in between?&nbsp;
&nbsp;
What Firmware version is currently loaded?https://kb.netgear.com/000036375/What-s-the-latest-firmware-version-of-my-NETGEAR-cable-modem-or-modem-routerPlease post a copy and paste of the modems event log page.https://kb.netgear.com/30008/How-do-I-view-or-clear-the-event-logs-on-my-NETGEAR-cable-modem-or-modem-routerBe sure your using a good quality LAN cable between the modem and router. CAT6A STP is recommended.&nbsp;What is the brand and model of the host wifi router connected to the modem?&nbsp;

dannoz · Answer

It's connected directly to a UniFi cloud gateway Max. The speed test is run on the router directly connected to the modem.

When I connect with the Comcast provided modem CBR2-T I get 1.4 Gbps down and 400 Mbps up.

When I change to the cm3000 the downstream stays the same and the upstream drops to 35 Mbps. Firmware V5.01.02.

Comcast business is now saying that the CM3000 modem only supports 35 Mbps upstream.

FURRYe38 · Answer

Sounds like you'll need to use there modem on there business line.&nbsp;

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CM3000 Comcast Business Slow Upload

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