diff --git a/freedata_server/arq_session.py b/freedata_server/arq_session.py
index 2164096e..73b9fa07 100644
--- a/freedata_server/arq_session.py
+++ b/freedata_server/arq_session.py
@@ -19,10 +19,10 @@ class ARQSession:
             'bandwidth': 250,
         },
         1: {
-            'mode': codec2.FREEDV_MODE.datac3,
+            'mode': codec2.FREEDV_MODE.data_ofdm_500,
             'min_snr': 0,
             'duration_per_frame': 3.19,
-            'bandwidth': 563,
+            'bandwidth': 500,
         },
         2: {
             'mode': codec2.FREEDV_MODE.datac1,
diff --git a/freedata_server/codec2.py b/freedata_server/codec2.py
index 606d93e0..63448897 100644
--- a/freedata_server/codec2.py
+++ b/freedata_server/codec2.py
@@ -541,12 +541,12 @@ data_ofdm_500_config.config.contents.tcp = 0.006
 data_ofdm_500_config.config.contents.ts = 0.016
 data_ofdm_500_config.config.contents.rs = 1.0 / data_ofdm_500_config.config.contents.ts
 data_ofdm_500_config.config.contents.nc = 8
-data_ofdm_500_config.config.contents.nuwbits = 40
 data_ofdm_500_config.config.contents.timing_mx_thresh = 0.10
-data_ofdm_500_config.config.contents.bad_uw_errors = 10
-data_ofdm_500_config.config.contents.codename = "H_4096_8192_3d".encode('utf-8')
+data_ofdm_500_config.config.contents.bad_uw_errors = 8
+data_ofdm_500_config.config.contents.codename = "H_1024_2048_4f".encode('utf-8')
 data_ofdm_500_config.config.contents.amp_scale = 305E3
-data_ofdm_500_config.config.contents.tx_uw = create_tx_uw(40, [0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 1])
+data_ofdm_500_config.config.contents.nuwbits = 32
+data_ofdm_500_config.config.contents.tx_uw = create_tx_uw(32, [0, 0, 1, 1, 1, 0, 1, 0, 1, 1, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1])
 data_ofdm_500_config.config.contents.clip_gain1 = 2.4
 data_ofdm_500_config.config.contents.clip_gain2 = 0.9
 data_ofdm_500_config.config.contents.tx_bpf_en = True