It would be best to know if others in your DMA have sound out of sync using OTA (antenna). If so the problem is clearly with the station and so contact them.
Otherwise the problem is with DISH or the feed being sent to dish by the local. In either of these later cases its better to contact DISH.
Are all of your locals out of sync. If so, it is Dish. If only one channel is out of sync, it is the station. First check your audio cables. Are they hooked up differently than the regular Dish channels. Like through an audio video receiver. This could cause the audio to delay.