diff --git a/check_iperf3.sh b/check_iperf3.sh
index 899d176..4037de5 100755
--- a/check_iperf3.sh
+++ b/check_iperf3.sh
@@ -19,6 +19,11 @@ if ! command -v iperf3 &>/dev/null; then
   exit 3
 fi
 
+if ! command -v jq &>/dev/null; then
+  echo "UNKNOWN - jq is not installed"
+  exit 3
+fi
+
 if [[ $# -eq 0 ]]; then
   print_help
 fi
@@ -81,7 +86,8 @@ if ! echo "$RESULT" | jq -e '.end.sum.bits_per_second' >/dev/null; then
   exit 3
 fi
 
-SPEED_RAW=$(echo "$RESULT" | jq '.end.sum.bits_per_second / 1000000')
+STREAM_RESULT=$(echo "$RESULT" | jq '.end.streams[] | select(.udp.sender == (!0)) | .udp.bits_per_second')
+SPEED_RAW=$(echo "$STREAM_RESULT" | jq 'if length > 0 then . / 1000000 else 0 end')
 SPEED=$(printf "%.0f" "$SPEED_RAW")
 
 if (($(echo "$SPEED < $CRITICAL" | bc -l))); then