diff --git a/legacy_tests/app_test_i2s_loopback/Makefile b/legacy_tests/app_test_i2s_loopback/Makefile
index 51bec388..7fb0bb12 100644
--- a/legacy_tests/app_test_i2s_loopback/Makefile
+++ b/legacy_tests/app_test_i2s_loopback/Makefile
@@ -63,7 +63,7 @@ BUILD_FLAGS_tdm_master_16in_16out_48khz = $(BUILD_FLAGS) -D XUA_PCM_FORMAT=XUA_P
   -D DEFAULT_FREQ=48000 \
   -O2 # optimisations to meet timing
 
-BUILD_FLAGS_tdm_slave_16in_16out_48khz = $(BUILD_FLAGS) -D XUA_PCM_FORMAT=XUD_PCM_FORMAT_TDM \
+BUILD_FLAGS_tdm_slave_16in_16out_48khz = $(BUILD_FLAGS) -D XUA_PCM_FORMAT=XUA_PCM_FORMAT_TDM \
   -D ADAT_RX=0 -D ADAT_TX=0 -D SPDIF_RX=0 -D SPDIF_TX=0 -D MIDI=0 \
   -D NUM_USB_CHAN_IN=16 -D NUM_USB_CHAN_OUT=16 -D I2S_CHANS_ADC=16 -D I2S_CHANS_DAC=16 \
   -D DEFAULT_FREQ=48000 -DCODEC_MASTER=1 \