I recommend trying 5mbps A protocol with maximum possible latency (just use default settings of "Preloaded demo" in PP Wireless Configurator).
PP EB with 8520-2590-EMs and nice antennas (Antenovas shipped with the kit are measly, to be frank) is able to throw 32khz audio at 300+ meters, though not as much with 44khz. Make sure you did not mix up antennas with, say, ISM ones (just in case, I did it once).
BR
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