Thanks
SShowron
Sorry for replying late, I was away for vacation so I left the ADSL as it was.
Make sure your ADSL is set as external (don't know why it isn't if it has a default gateway)
Well only Cable is set as External automatically, can I give different Default Gateway for both external Connections. would it make some problem.
Make sure the 'Dead Gateway detection' is ticked in the ENS Settings and it will fall-over to the ADSL if the cable goes out
Yes, this seems to be the solution, I will make the changes as suggested by you. and then come back with the result.