Problematic Router/Modem

The ping latency on my connection has been all over the place recently with pages on the internet slow, hanging or refusing to load at all. My ISP ran tests today and after advising me to disconnect my computers and devices, both wired and wireless, for an hour, they reported data being uploaded and some traffic being downloaded. It was suggested that this might be the router/modem trying to automatically download firmware. I'm using a dinosaur, the Netgear DGN1000 (not sure what version), but I am wondering should I bother with downloading any firmware or just join the 21st century and upgrade to something newer?

In advance, thanks for any assistance.

Is it possible someone else is latching onto your wireless?

First, thanks for taking the time to respond!

I wondered the same thing. Perhaps I am being naive, but I have a rather complex password, does that count for anything? Should I change the password? Wouldn't it make more sense that if someone hacked my router/modem they would use it for downloads and not uploads?

What if they a seed site for torrents? Or upload a lot of photos and videos - those have changed usage patters a lot, both cloud backups and YouTube.

High uploads will kill your download speeds as they leave no upstream bandwith for your system's ACKs and complex site browsing data requests.

You should be able to find what is connected to your wifi in your router GUI.

Depending on the number of devices might be worth restricting my MAC address if possible?

In addition ensure you have a complex password for the router admin account...