Trouble with ZyXEL VMG1312-B10A modems

Had two of the above modems and both have failed at one stage or another. First one bricked itself after turning the power on and off a couple of times because it had locked up and couldn't get it into recovery mode or factory reset. So replaced that with another because they give the highest sync on my FTTC line.

Today the second one went faulty at 7.33am and started constantly rebooting. Turned out it was the PSU only putting out 11v instead of 12v. So swapped the PSU from the first bricked modem and all is working again. But how long for.

Anyone else have a poor experience of ZyXEL modems?

Have ordered another of the above but this one is a new iTalk version so maybe locked to their service. I know how to unlock it but anyone heard of iTalk before?

https://www.italktelecom.co.uk/

Thanks for the link. I googled that a few days ago but it's a very basic site and support pages are pretty limited.

So I took delivery of a brand new 1312 italk branded router. It wouldn't accept the standard admin password despite the italk documentation saying it was that. I did a factory reset and bang we're in with default password.

Interesting to note it was on V6 of the firmware so upgraded that to V12 and loaded a backup configuration from disk. Interesting to note that the backup configuration must contain the supervisor password as I can now log in with my password from my other router on V12 after loading the config file.

Only tested for 10 minutes but seems to sync a little slower at 68½ down whereas the other older one syncs at 71½ and after I swapped them back the old one showed the same sync. Must admit not extensive testing of the new spare one could have been a bad retrain but it is a spare in case the old one goes pop.

I have been having message tennis with the seller of the above router that is broke and he insisted no returns no refunds. I have discovered the device was made in 2015 so well out of the manufacturer's warranty.
So I opened an eBay case and eBay has instructed me to send it back to the seller, even gave me a printed return label which I imagine the cost will come off any refund given.
It is tracked and Royal Mail now has it at the post office, only hope he doesn't reject the parcel or is in to take delivery as eBay have said they will refund as soon as the tracking is complete.