diff --git a/examples/pbch_ue.c b/examples/pbch_ue.c
index fedb9c345..e2f82bbf9 100644
--- a/examples/pbch_ue.c
+++ b/examples/pbch_ue.c
@@ -58,7 +58,7 @@
 #define NOF_PORTS 2
 
 float find_threshold = 40.0, track_threshold = 8.0;
-int max_track_lost = 9, nof_slots = -1;
+int max_track_lost = 20, nof_slots = -1;
 int track_len=300;
 char *input_file_name = NULL;
 int disable_plots = 0;
@@ -80,7 +80,7 @@ cfo_t cfocorr;
 enum sync_state {FIND, TRACK};
 
 void usage(char *prog) {
-	printf("Usage: %s [iagfndv]\n", prog);
+	printf("Usage: %s [iagfndvp]\n", prog);
 	printf("\t-i input_file [Default use USRP]\n");
 #ifndef DISABLE_UHD
 	printf("\t-a UHD args [Default %s]\n", uhd_args);
@@ -90,6 +90,7 @@ void usage(char *prog) {
 	printf("\t   UHD is disabled. CUHD library not available\n");
 #endif
 	printf("\t-n nof_frames [Default %d]\n", nof_slots);
+	printf("\t-p PSS threshold [Default %f]\n", find_threshold);
 #ifndef DISABLE_GRAPHICS
 	printf("\t-d disable plots [Default enabled]\n");
 #else
@@ -100,7 +101,7 @@ void usage(char *prog) {
 
 void parse_args(int argc, char **argv) {
 	int opt;
-	while ((opt = getopt(argc, argv, "iagfndv")) != -1) {
+	while ((opt = getopt(argc, argv, "iagfndvp")) != -1) {
 		switch(opt) {
 		case 'i':
 			input_file_name = argv[optind];
@@ -114,6 +115,9 @@ void parse_args(int argc, char **argv) {
 		case 'f':
 			uhd_freq = atof(argv[optind]);
 			break;
+		case 'p':
+			find_threshold = atof(argv[optind]);
+			break;
 		case 'n':
 			nof_slots = atoi(argv[optind]);
 			break;
@@ -423,7 +427,9 @@ int main(int argc, char **argv) {
 				find_idx += track_idx - track_len;
 				if (nslot != sync_get_slot_id(&strack)) {
 					INFO("Expected slot %d but got %d\n", nslot, sync_get_slot_id(&strack));
-					printf("\r\n");fflush(stdout);
+					printf("\r\n");
+					fflush(stdout);
+					printf("\r\n");
 					state = FIND;
 				}
 			}
@@ -431,7 +437,9 @@ int main(int argc, char **argv) {
 			/* if we missed too many PSS go back to FIND */
 			if (frame_cnt - last_found > max_track_lost) {
 				INFO("%d frames lost. Going back to FIND", frame_cnt - last_found);
-				printf("\r\n");fflush(stdout);
+				printf("\r\n");
+				fflush(stdout);
+				printf("\r\n");
 				state = FIND;
 			}
 
@@ -447,6 +455,9 @@ int main(int argc, char **argv) {
 					last_found = frame_cnt;
 					if (verbose == VERBOSE_NONE) {
 						if (!nof_found_mib) {
+							printf("\r\n");
+							fflush(stdout);
+							printf("\r\n");
 							pbch_mib_fprint(stdout, &mib);
 						}
 					}
diff --git a/examples/scan_mib.c b/examples/scan_mib.c
index 16654ff53..90bec1080 100644
--- a/examples/scan_mib.c
+++ b/examples/scan_mib.c
@@ -53,11 +53,11 @@
 #define IS_SIGNAL(i) (10*log10f(rssi[i]) + 30 > rssi_threshold)
 
 int band, earfcn=-1;
-float find_threshold = 40.0, track_threshold = 8.0;
+float find_threshold = 10.0, track_threshold = 8.0;
 int earfcn_start=-1, earfcn_end = -1;
-float rssi_threshold = -30.0;
+float rssi_threshold = -45.0;
 int max_track_lost=9;
-int nof_frames_find=8, nof_frames_track=100, nof_samples_rssi=50000;
+int nof_frames_find=20, nof_frames_track=100, nof_samples_rssi=50000;
 int track_len=500;
 
 cf_t *input_buffer, *fft_buffer, *ce[MAX_PORTS];
@@ -72,7 +72,7 @@ int *idx_v, *idx_valid, *t;
 float *p2a_v;
 void *uhd;
 int nof_bands;
-float uhd_gain = 30.0;
+float uhd_gain = 20.0;
 
 #define MAX_EARFCN 1000
 lte_earfcn_t channels[MAX_EARFCN];
@@ -232,7 +232,7 @@ void base_free() {
 	int i;
 
 #ifndef DISABLE_UHD
-	cuhd_close(&uhd);
+	cuhd_close(uhd);
 #endif
 
 	sync_free(&sfind);
diff --git a/examples/scan_pss.c b/examples/scan_pss.c
index 599a6cb06..fb754acab 100644
--- a/examples/scan_pss.c
+++ b/examples/scan_pss.c
@@ -49,11 +49,11 @@
 
 
 int band, earfcn=-1;
-float find_threshold = 40.0, track_threshold = 8.0;
+float find_threshold = 10.0, track_threshold = 8.0;
 int earfcn_start=-1, earfcn_end = -1;
-float rssi_threshold = -30.0;
+float rssi_threshold = -45.0;
 int max_track_lost=9;
-int nof_frames_find=8, nof_frames_track=100, nof_samples_rssi=50000;
+int nof_frames_find=20, nof_frames_track=100, nof_samples_rssi=50000;
 int track_len=500;
 
 cf_t *input_buffer;
@@ -184,7 +184,7 @@ int base_init(int frame_length) {
 
 void base_free() {
 
-	cuhd_close(&uhd);
+	cuhd_close(uhd);
 	free(input_buffer);
 	free(idx_v);
 	free(idx_valid);
diff --git a/lte/include/lte/modem/demod_hard.h b/lte/include/lte/modem/demod_hard.h
index 4525ff7a1..c7608b5d8 100644
--- a/lte/include/lte/modem/demod_hard.h
+++ b/lte/include/lte/modem/demod_hard.h
@@ -54,7 +54,7 @@ typedef struct {
 		enum modem_std std;		// Symbol mapping standard (see modem_table.h)
 	} init;
 
-	const cf_t* input;
+	cf_t* input;
 	int in_len;
 
 	char* output;
diff --git a/lte/lib/common/src/lte.c b/lte/lib/common/src/lte.c
index 8147b68d1..e475cf161 100644
--- a/lte/lib/common/src/lte.c
+++ b/lte/lib/common/src/lte.c
@@ -30,6 +30,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 #include "lte/common/base.h"
 
@@ -156,6 +157,7 @@ char *lte_mimotype2str(mimo_type_t type) {
 	case SPATIAL_MULTIPLEX:
 		return "multiplex";
 	}
+	return NULL;
 }
 
 float get_fd(struct lte_band *band, int earfcn) {
diff --git a/lte/lib/mimo/src/precoding.c b/lte/lib/mimo/src/precoding.c
index 4bb5176eb..fad5947c0 100644
--- a/lte/lib/mimo/src/precoding.c
+++ b/lte/lib/mimo/src/precoding.c
@@ -53,8 +53,29 @@ int precoding_diversity(cf_t *x[MAX_LAYERS], cf_t *y[MAX_PORTS], int nof_ports,
 		}
 		return i;
 	} else if (nof_ports == 4) {
-		fprintf(stderr, "Error not implemented\n");
-		return -1;
+		int m_ap = (nof_symbols%4)?(nof_symbols*4-2):nof_symbols*4;
+		for (i=0;i<m_ap;i++) {
+			y[0][4*i] = x[0][i]/sqrtf(2);
+			y[1][4*i] = 0;
+			y[2][4*i] = -conjf(x[1][i])/sqrtf(2);
+			y[3][4*i] = 0;
+
+			y[0][4*i+1] = x[1][i]/sqrtf(2);
+			y[1][4*i+1] = 0;
+			y[2][4*i+1] = conjf(x[0][i])/sqrtf(2);
+			y[3][4*i+1] = 0;
+
+			y[0][4*i+2] = 0;
+			y[1][4*i+2] = x[2][i]/sqrtf(2);
+			y[2][4*i+2] = 0;
+			y[3][4*i+2] = -conjf(x[3][i])/sqrtf(2);
+
+			y[0][4*i+3] = 0;
+			y[1][4*i+3] = x[3][i]/sqrtf(2);
+			y[2][4*i+3] = 0;
+			y[3][4*i+3] = conjf(x[2][i])/sqrtf(2);
+		}
+		return i;
 	} else {
 		fprintf(stderr, "Number of ports must be 2 or 4 for transmit diversity\n");
 		return -1;
@@ -111,7 +132,7 @@ int predecoding_diversity_zf(cf_t *y[MAX_PORTS], cf_t *ce[MAX_PORTS],
 	cf_t h0, h1, r0, r1;
 	float hh;
 	if (nof_ports == 2) {
-		/* FIXME: Use VOLK here */
+		/* TODO: Use VOLK here */
 		for (i=0;i<nof_symbols/2;i++) {
 			h0 = ce[0][2*i];
 			h1 = ce[1][2*i];
@@ -124,6 +145,29 @@ int predecoding_diversity_zf(cf_t *y[MAX_PORTS], cf_t *ce[MAX_PORTS],
 		}
 		return i;
 	} else if (nof_ports == 4) {
+		/*
+		int m_ap = (nof_symbols%4)?((nof_symbols-2)/4):nof_symbols/4;
+		for (i=0;i<m_ap;i++) {
+			h0 = ce[0][2*i];
+			h1 = ce[1][2*i];
+			h2 = ce[2][2*i];
+			h3 = ce[3][2*i];
+			hh = crealf(h0)*crealf(h0)+cimagf(h0)*cimagf(h0)
+					+ crealf(h1)*crealf(h1)+cimagf(h1)*cimagf(h1)
+					+ crealf(h2)*crealf(h2)+cimagf(h2)*cimagf(h2)
+					+ crealf(h3)*crealf(h3)+cimagf(h3)*cimagf(h3);
+			r0 = y[0][2*i];
+			r1 = y[0][2*i+1];
+			r2 = y[0][2*i+2];
+			r3 = y[0][2*i+3];
+
+			x[0][i] = (conjf(h0)*r0 + conjf(h1)*r1)/hh * sqrt(2);
+			x[1][i] = (h1*conj(r0) + conj(h0)*r1)/hh * sqrt(2);
+			x[2][i] = (conjf(h0)*r0 + h1*conjf(r1))/hh * sqrt(2);
+			x[3][i] = (-h1*conj(r0) + conj(h0)*r1)/hh * sqrt(2);
+
+		}
+		*/
 		fprintf(stderr, "Error not implemented\n");
 		return -1;
 	} else {
diff --git a/lte/lib/ratematching/test/rm_conv_test.c b/lte/lib/ratematching/test/rm_conv_test.c
index a7d9a47e1..dc79ecceb 100644
--- a/lte/lib/ratematching/test/rm_conv_test.c
+++ b/lte/lib/ratematching/test/rm_conv_test.c
@@ -112,6 +112,7 @@ int main(int argc, char **argv) {
 		exit(-1);
 	}
 
+	nof_errors = 0;
 	for (i=0;i<nof_tx_bits;i++) {
 		if ((unrm_symbols[i] > 0) != bits[i]) {
 			nof_errors++;
diff --git a/lte/lib/utils/src/cexptab.c b/lte/lib/utils/src/cexptab.c
index 235b69389..d1e13ab93 100644
--- a/lte/lib/utils/src/cexptab.c
+++ b/lte/lib/utils/src/cexptab.c
@@ -68,6 +68,9 @@ void cexptab_gen(cexptab_t *h, cf_t *x, float freq, int len) {
 		if (phase >= (float) h->size) {
 			phase -= (float) h->size;
 		}
+		if (phase <= 0) {
+			phase += (float) h->size;
+		}
 	}
 }