i have a soniq 32" plasma hd tv ?

I turned it on with the remote there was picture and sound for about 1min then it just went blank. The blue light was showing as if it were still on so I tried changing the channels but still nothing. I turned it off for 5mins then back on again this time the blue light (indicating tv is on) didnt show up. I changed the batteries in the remote and nothing. I checked batteries were OK and yes, they were fine.

So, I have standby red light on, but tv wont switch on, any thoughts please??? thank you