Balance 20X router continually fails

From the 5G store, a reliable and reputable vendor, I bought a Peplink Soho Surfer in 12/2020. It has worked reliably since purchase. Because download is limited to about 120-130 Mbps, I upgraded in 12/2021 to the Balance 20x to take advantage of the 240 Mbps offered by Spectrum, which provided a Technicolor DPC 3216 modem (Docsis 3.0 16X4). I am using latest firmware 8.2. Should I revert back to previous firmware if it is available?
My setup is typical for a small business: 4-system hardwired Ethernet LAN with 3 TVs on the attached wifi SSID. The Soho Surfer had no issues with the setup. The first Balance 20x lasted about 3 months when it regularly started failing on internet connection to 2 or more of the systems.
The second Balance 20x lasted about a year when internet also began to fail. The third replacement, probably new lasted till today, when I added a VLAN so that I could assign the TVs to the VLANs wifi SSID. Shortly after that, the Balance 20X would not provide any internet connection, though modem was working fine, based on direct connection to one system.
Multiple reboots of both modem and Balance 20x (and reset of router) did not restore internet connection from Balance 20x. So I am back to the Soho Surfer. There seems to be an incompatibility issue between Balance 20x and my Technicolor modem. Are there any logs of the modem or Balance 20x that would shed light on the issue?
Or perhaps are there settings in the Pepwave admin software that I should be using?

I got a Peplink router in the first place because of solid security: 1) updated firmware; and 2) Peplink routers don’t seem to phone in data. Both Peplink and 5G Store have worked to help me but to no avail. I would hate to have to get a modem/router from Spectrum–totally insecure.
Thanks to the experts.

We have about 50 Balance 20X routers in the field, have only had 1 RMA which was a DOA. We have mix of HW1, HW2 and HW3, don’t see any reliability difference between them.

So not sure what is happening with yours. Maybe something with your power causing issues?

I upgrade from a Balance 30 LTE to a 20x + mini module CAT12

It’s quite catastrophic in performance and stability, ticket and investigations opens

Balance 30 LTE CAT4 outperforms the 20x, night and day

We are using the B20X with the CAT18 or 5G modules. They perform well and way better than the CAT6 modems we had before in the BR1 ENT/HD2.

The built-in CAT4 is not the fastest of course, but in combination with the CAT18 I can still get enough performance out of it. We also use the 20X with wired uplinks, 1Gbps fiber is no problem, get above 900Mbps Router throughput.

We are in Europe, not sure which region you are in, but the models/modems differ per region.

Perhaps faulty material but quite disapointing for instant

We’ll see