diff --git a/rootfs/etc/s6-overlay/scripts/dump978 b/rootfs/etc/s6-overlay/scripts/dump978
index ea6442c..5ae904a 100755
--- a/rootfs/etc/s6-overlay/scripts/dump978
+++ b/rootfs/etc/s6-overlay/scripts/dump978
@@ -52,7 +52,8 @@ if [[ -n "$READSB_SDR_GAIN" ]]; then
     sleep 3 # let autogain do its inital thing
     if [[ "${READSB_SDR_GAIN,,}" == "autogain" ]] && [[ -f /var/globe_history/autogain/gain ]]; then
         read -r gain < /var/globe_history/autogain/gain
-        DUMP978_CMD+=("--sdr-gain $gain") 
+        gain="${gain:-${DUMP978_AUTOGAIN_INITIAL_GAIN:-${READSB_AUTOGAIN_INITIAL_GAIN:-49.6}}}"
+        DUMP978_CMD+=("--sdr-gain $gain")
     elif [[ -n "$READSB_SDR_GAIN" ]]; then
         [[ "${READSB_SDR_GAIN,,}" == "autogain" ]] && gain="${DUMP978_AUTOGAIN_INITIAL_GAIN:-${READSB_AUTOGAIN_INITIAL_GAIN:-49.6}}" || gain="${READSB_SDR_GAIN}"
         DUMP978_CMD+=("--sdr-gain $gain")