Gas fireplace doesn't always turn on
I have a gas fireplace I have recently turned on for the season. Occationally when I turn on the switch the fireplace does not light the gas tubes. After maybe the 3rd try the fireplace turns on. The pilot light is is always lit, there is NOT an issue with the pilot light going out. The fireplace has been turned on successfully several times with FULL flame this season. The switch to turn on the fireplace is on the wall. Thoughts?