Problem with net connect - Linksys

For the past two days I've been having trouble staying connected on the
net. Connection seems slow or stops altogether.
To remedy the problem I sometimes disconnect the power-lead to the Gateway,
reconnect and then via //192.168.1.1/ (tab status) I press the connect
button. This seems to remedy the problem for a while.

I'm not sure if its and ISP problem or a problem with the hardware.

The lights for ADSL and Session are steady, while Act is blinking.

Are there any steps I can do to check if everything's o.k with the Gateway?
Its a Linksys WAG54G

Thank you