Hi @rogerfor7 and welcome to the Grafana forum.
There are probably many ways to do this, but personally I would set up a webhook contact point…
…then run Node-RED on the computer that is being displayed on your TV. Then, use Node-RED to receive the webhook and play a given audio file once an alert is received. Because Node-RED can pretty much do anything (except make you breakfast), you can also have lights flash, Tweets sent out, etc.
I actually have been meaning to do this myself, so will report back on this thread once I have it up and running.