Let's call short bursts of data packets (because that’s really what they are). In packet transmissions, there are a few ways of ensuring that the synchronizers have enough time to lock up. The easiest way for you to go about this, is adding a packet header that carries no information, such as 101010101, but can be used by the sync blocks to synchronize. The sync blocks require transitions to make the magic happen. If you add this in front of all your real data bursts, you will lose some of those SYNC frame bits each time, but you don't care about that because it's not real data AND the synchronizers will be locked by the time the real data starts.