diff --git a/src/modules/modem/analog/ModemUSB.cpp b/src/modules/modem/analog/ModemUSB.cpp
index a03f46d..940cbb3 100644
--- a/src/modules/modem/analog/ModemUSB.cpp
+++ b/src/modules/modem/analog/ModemUSB.cpp
@@ -56,9 +56,8 @@ void ModemUSB::demodulate(ModemKit *kit, ModemIQData *input, AudioThreadInput *a
         nco_crcf_mix_down(ssbShift, input->data[i], &x);
 		iirfilt_crcf_execute(ssbFilt, x, &y);
 		nco_crcf_mix_up(ssbShift, y, &x);
-        // TODO: use fixed firhilbf_c2r usb param to simplify instead of shifting and discarding
-        float usb_discard;
-        firhilbf_c2r_execute(c2rFilt, x, &demodOutputData[i], &usb_discard);
+        float lsb_discard;
+        firhilbf_c2r_execute(c2rFilt, x, &lsb_discard, &demodOutputData[i]);
     }
     
     buildAudioOutput(akit, audioOut, true);