Another thing it could be is that there is a small switch behind the jack sockets terminals that cuts out the speakers when you plug the phones in and makes a power contact for the phone light.
Now that could be just stuck enough to keep the speakers cut out and that light on. If you can get behind the panel use a strong light to look closely at the terminals at that phone socket. You may be able just to flick it with a plastic probe of some sort - Biro pen will do but however maybe unlucky enough to have a switching mechanism that it encased and then it may be released by some gentle
tapping or worse case scenario - replace.
But look for AddRAM's advice first but I do think it is a hardware issue as I have been messing with dedicated electronics for errrrm a long time
Sorry I did notice also that you have a laptop in that case unless you can get to the back of that switch yourself ( depends on how handy you are) someitmes a a few quick in and outs of the jack plug can dislodhge the switch.