diff --git a/hardware/AFSK.c b/hardware/AFSK.c
index 8ee360f..eb8c1ed 100755
--- a/hardware/AFSK.c
+++ b/hardware/AFSK.c
@@ -602,7 +602,6 @@ void AFSK_adc_isr(Afsk *afsk, int8_t currentSample) {
 }
 
 inline void timed_functions(void) {
-    update_led_status();
     if (_clock % CLOCK_TICKS_PER_10_MS == 0) {
         sd_scheduler();
     }
@@ -625,11 +624,12 @@ ISR(TIMER3_CAPT_vect) {
 ISR(ADC_vect) {
     TIFR1 = _BV(ICF1);
     
-    if (CONFIG_FULL_DUPLEX || !hw_afsk_dac_isr) {
+    if (!hw_afsk_dac_isr) {
         AFSK_adc_isr(AFSK_modem, (ADCH - 128));
+        timed_functions();
     }
 
-    timed_functions();
+    update_led_status();
 
     ++_clock;
 }
\ No newline at end of file
diff --git a/hardware/AFSK.h b/hardware/AFSK.h
index 7423a0f..acdb065 100755
--- a/hardware/AFSK.h
+++ b/hardware/AFSK.h
@@ -9,6 +9,7 @@
 #include "util/FIFO.h"
 #include "protocol/HDLC.h"
 
+// TODO: Optimise RAM by moving this to progmem
 #define SIN_LEN 512
 static const uint8_t sine_table[] =
 {