diff --git a/firmware/user/src/touch.c b/firmware/user/src/touch.c
index 2e849ef..941034d 100644
--- a/firmware/user/src/touch.c
+++ b/firmware/user/src/touch.c
@@ -21,20 +21,24 @@ uint16_t touch_read_adc(u8 adc_ch)
     TBTN_ADC->IDATAR1 = 0x10;  // charging time
     TBTN_ADC->RDATAR  = 0x08;  // discharging time
 
+    ADC_SoftwareStartConvCmd(TBTN_ADC, ENABLE);
     while(!ADC_GetFlagStatus(TBTN_ADC, ADC_FLAG_EOC));
     return (uint16_t)TBTN_ADC->RDATAR;
 }
 
 uint16_t touch_read(u8 btn_ch)
 {
-    if (btn_ch < 2) return touch_read_adc(tbtn_adc_ch[btn_ch]);
+    if (btn_ch < TBTN_COUNT) return touch_read_adc(tbtn_adc_ch[btn_ch]);
     else return 0xffff;
 }
 
 uint8_t touch_read_pushed(uint8_t btn_ch)
 {
-    if (touch_read_adc(tbtn_adc_ch[btn_ch]) < tbtn_idle_cal[btn_ch] - TBTN_PUSHED_COUNTS)
+    if (btn_ch > 1) return 0;
+
+    if (touch_read_adc(tbtn_adc_ch[btn_ch]) < tbtn_idle_cal[btn_ch] - TBTN_PUSHED_COUNTS) {
         return 1;
+    }
 
     return 0;
 }
@@ -42,24 +46,26 @@ uint8_t touch_read_pushed(uint8_t btn_ch)
 void touch_cal()
 {
     uint8_t i, j;
-    uint16_t val;
+    uint32_t val;
 
-    for (i = 0; i < 2; i++) {
-        val = 0xffff;
-        while (val > TBTN_IDLE_WINDOW_HI) {
-            // be warned,
-            // we can hang here until the buttons can be calibrated
+    for (i = 0; i < TBTN_COUNT; i++) {
+        // do a dummy read
+        touch_read(tbtn_adc_ch[i]);
+
+        // hang until the button appears to be idle
+        val = 0;
+        while (val < TBTN_IDLE_LOW_VAL) {
             val = touch_read(tbtn_adc_ch[i]);
         }
 
-        // get average of 8 readings
+        // get average of 4 readings and store as calibration value
         val = 0;
-        for (j = 0; j < 8; j++) {
+        for (j = 0; j < 4; j++) {
             val += touch_read(tbtn_adc_ch[i]);
         }
-        val >>= 3;
+        val >>= 2;
 
-        tbtn_idle_cal[i] = val;
+        tbtn_idle_cal[i] = val & 0xfff;
     }
 }
 
diff --git a/firmware/user/src/touch.h b/firmware/user/src/touch.h
index 31a9604..ef7913f 100644
--- a/firmware/user/src/touch.h
+++ b/firmware/user/src/touch.h
@@ -12,13 +12,13 @@
 
 #define TBTN_ADC                ADC2
 
+#define TBTN_COUNT              2
+
 #define TBTN1                   ADC_Channel_4       // right button
 #define TBTN2                   ADC_Channel_9       // left button
 
-#define TBTN_IDLE_WINDOW_LO     300
-#define TBTN_IDLE_WINDOW_HI     500
-
-#define TBTN_PUSHED_COUNTS      100
+#define TBTN_IDLE_LOW_VAL       0xfd0               // values above this == not touched. used to calibrate
+#define TBTN_PUSHED_COUNTS      0x37f               // counts must drop below tbtn_idle_cal-TBTN_THRESHOLD to be considered a press
 
 
 #define ADC_CTLR1_TKENABLE      (1 << 24)