@zageng 

Good day.

Thank you very much for your time and patience.

For your case, we might need your help to check the following information:

Did the unstable connection start after the firmware update?

Who is your internet service provider and At the back of the VR400, is it the DSL port connected to the internet provider, or the Ethernet port?

When the internet dropped, is there any change on the LED lights on the modem?

Have you ever noticed that if both wired connections and wireless connections have the same issue or just wireless?

Thank you very much!