diff --git a/nanovna.h b/nanovna.h
index fc52518..c432e27 100644
--- a/nanovna.h
+++ b/nanovna.h
@@ -1191,7 +1191,7 @@ typedef int16_t  pureRSSI_t;
 #ifdef TINYSA4
 #define EXT_ZERO_LEVEL            (174)
 #else
-#define EXT_ZERO_LEVEL            (174)
+#define EXT_ZERO_LEVEL            (128)
 #endif
 #define DEVICE_TO_PURE_RSSI(rssi) ((rssi)<<4)
 #define PURE_TO_DEVICE_RSSI(rssi) ((rssi)>>4)
diff --git a/sa_core.c b/sa_core.c
index 13a3c7e..1d1ce07 100644
--- a/sa_core.c
+++ b/sa_core.c
@@ -661,7 +661,7 @@ void set_level(float v)     // Set the output level in dB  in high/low output
   if (setting.mode == M_GENHIGH) {
     int d = 0;
     v = v - config.high_level_output_offset;
-    while (drive_dBm[d] < v - 1 && (unsigned int)d < (sizeof(drive_dBm)/sizeof(int))-1 )
+    while (drive_dBm[d] < v - 1 && (unsigned int)d < (sizeof(drive_dBm)/sizeof(drive_dBm[0]))-1 )
       d++;
 //    if (d == 8 && v < -12)  // Round towards closest level
 //      d = 7;
@@ -3911,7 +3911,7 @@ int validate_atten(int i) {
       reference_peak_level = summed_peak_level;
     else {
 //      if (SDU1.config->usbp->state == USB_ACTIVE)  shell_printf("Attenuation %.2fdB, measured level %.2fdBm, delta %.2fdB\n\r",a, summed_peak_level, summed_peak_level - reference_peak_level);
-#define ATTEN_TEST_CRITERIA 1
+#define ATTEN_TEST_CRITERIA 1.5
       if (summed_peak_level - reference_peak_level <= -ATTEN_TEST_CRITERIA || summed_peak_level - reference_peak_level >= ATTEN_TEST_CRITERIA) {
         status = TS_FAIL;
  //       draw_all(true);
@@ -4009,6 +4009,9 @@ int test_validate(int i)
 
 void test_prepare(int i)
 {
+  setting.measurement = M_OFF;
+  markers[1].enabled = M_DISABLED;
+  markers[2].enabled = M_DISABLED;
   setting.tracking = false; //Default test setup
   setting.atten_step = false;
 #ifdef TINYSA4
@@ -4071,7 +4074,7 @@ common_silent:
     for (int j = 0; j < setting._sweep_points/2 - W2P(test_case[i].width); j++)
       stored_t[j] = test_case[i].stop;
     for (int j = setting._sweep_points/2 + W2P(test_case[i].width); j < setting._sweep_points; j++)
-      stored_t[j] = test_case[i].stop - (i == 6?5:0);
+      stored_t[j] = test_case[i].stop - (i == 6?3:0);
     for (int j = setting._sweep_points/2 - W2P(test_case[i].width); j < setting._sweep_points/2 + W2P(test_case[i].width); j++)
       stored_t[j] = test_case[i].pass;
     break;