450b issue

Hi I have a customer who has had some off and on issues and today has reached out to let me know that every 2-3 days they begin to have speed reductions and when they try a speed test they get about 3mbps of download and once they power cycle the antenna speeds return to normal and their speed test renders the 50mbps that they have for a speed. Any insight?
I do trust this customers troubleshooting skills and we have worked closely with this individual as they were our first customer when we launched a 450m for their area. We are running 22.1.1 on AP and SMs


We have been seeing this more and more often on our network as well. we have a couple hundred subscribers on both the 3.65 and 5ghz 450m’s and a power cycle seems to fix the 450b’s slowing down to nothing. We have seen this for the past 2 years firmware and keep on the current stable firmware version within 2 weeks of release.

@Robert_Saunders I really appreciate your reply. My customer reported great service for 4-5 days then reboot is required.
Could anyone at Cambium jump in on this? Is this an anomaly in certain radios and could be hardware related or is this something software related?

So there’s like a bazzillion of these PMP450b radios deployed… if this was a common issue don’t you think people would be reporting it?

Why don’t you do some basic troubleshooting?

What’s the link drop rate look like on the radio’s ethernet interface? What’s the error rate look like?
Are you using NAT on the radio? Have you tried changing any of the NAT table settings?
Have you tried bridge mode on the radio?
What about if the customer tries rebooting his router first, does that resolve the issue?
If the customer tries a different router, does that resolve the issue?

Come on man, do some homework.

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@Eric_Ozrelic lol… would definitely appreciate a less condescending reply but you do you.

I did not go into great detail in original post but I did say that once the antenna was power cycled problem was instantly solved.

He is seeing it, but do not disagree with your logic. I guess he should do more basic troubleshooting and homework but I was not going to assume he did not.

Not sure why you would automatically assume we had not but I get it, instead of a long winded post I got straight to it, power cycle the antenna problem solved.




Tried that and no

Not sure this was needed but like I said you do you :+1:

Appreciate you taking the time, cheers.

I apologize, it’s been a long day… and based on your initial posts I wasn’t sure what if any troubleshooting you’ve done.

Have you tried swapping out the radio for a new one?

Any other users on the AP report this issue and also have to reboot the SM in order to restore speeds?

What’s your AP’s frame utilization look like during peak hours when you review, day to day?

Are you using any other priority classes other then LOW prio for everyone? Are you using any other priority settings for that SM?

Do you have any upstream traffic shaping in place? Have you tried setting the radio’s MIR to a higher rate then what the upstream shaper is handling?

I’m grasping at straws here because the issue you’re presenting is not something that our ISP is experiencing and not something that I’ve seen come up in the forums.

Good morning, could you open a support ticket and include the AP and SM engineering.cgi log during the slowness for us analyze further? For the SM log, we would like to see before and after the reboot.

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@Cambium_Lena I will definitely do that. The customer is quick to let me know when the slowness happens. Thank you.

Hey @DigitalMan2020 , Just letting you know we’ve seen the same issue before. It usually is partnered with a specific message in the error log “QQ_Put with RFLinkSyncQueue has failed. Caller: 0x033b6c6c, MsgType: 0x000000ff, ExtType: 0x00000037” also found in this post Error Message: QQ_Put with RFLinkSyncQueue

Hopefully Cambium was able to get you sorted. I wouldn’t say this is super wide spread, but we’ve seen it on a handfull.

@Tandr06 thank you for posting this, I appreciate it! I have not submitted anything to cambium yet, just waiting for the issue to arise again.

As soon as you start seeing that issue again, I’d open a ticket. Got one back last week that had been having the issue. Opened an RMA ticket and was denied unfortunately. Frustrating because it’s not an issue caused by the operator.

Its reminiscent of those known vehicle issues (DFS system in my 2020 Silverado…) that the dealer knows about but hasn’t hit the threshold they have to report lol

@DigitalMan2020 We’re continuing to find radios with that QQ code. Had another call for it today actually. The one I recently had denied was from a batch in 6/2020. Spot checked a few other radios from this batch and have found 2 others with that error showing in the log. Now I’m checking through all the radios from that order to see if I can find more.

Fun project lol