That’s quite close to me, for Long Range LoRa radio. So, what if you increase that, a lot? Like 10 meters or more?
And are you sure the CRC errors are related to transmissions from your devices? (Rather than some other devices that happen to be in the neighbourhood.)
Did things ever work for you? When you leave the gateway Traffic page in TTN Console open for quite some time (or when you look in your logs over an extended period), are you seeing packets from other nodes?
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