3CRWER200-75 - ISP Connection & Wireless connection problem

[Jonny]

I have 3COM OfficeConnect Wireless 108 Mbps Cable/DSL Router.

With last firmware - 1.3.14ww.

1) It can't keep a connection with ISP - Regularly starts blink red light (about onсe every hour).

2) I have static IP from my ISP. And each time when device reboots (not reset), WAN connection settings reset to their defaults (instead of configured static address appears dynamic).

3) Constantly experiencing problems with connecting some Wi-Fi devices (laptops, phones ...). Some devices can not connect to the router,  Some devices show established connection, but Internet isn't working.

The device is operated in a fairly good conditions. It did not fall, and it does not hurt
When I connect the ISP directly to the computer, everything works well.

    What should I do?

And please, do not consult to look the settings, ping, traceroute or ipconfig... :-) I'm sysadmin, so I tried all possible methods.

More than one year ago, when I was install a new firmware (at the time) I first encountered these problems (disconnects from ISP and Wi-Fi connection problem). 

 Pretty girl in tech support told me that this hardly can be and I'm doing something wrong. Very strange answer, especially considering that I had three such routers, and they were bought at different locations during six months. => Support unprofessional.

Now I doubt that'll buy something from 3COM, and no one will advise.

But was a time when 3COM did a professional and quality devices. :(

P.S. I do not want to throw them in the trash. Therefore, the last time I use them not as a router, but only as a wireless access point (and then only for those devices that can connect to them)

[Techno]

Johnny

Check the router logs when the Alert light comes up, sounds like your fixed IP is now Attacks Target.

Too many attacks will food the logs on the router and cause a reboot.

Try setting the router to log to a syslog only, see if that helps you, it will release more memory reducing the reboot issue.

Meanwhile, tell your ISP to clean his network, too many attacks is not good.

PS: Make sure your router does not respond to Ping either.