diff --git a/src/hfp.h b/src/hfp.h
index 7f3930a0a..883012be4 100644
--- a/src/hfp.h
+++ b/src/hfp.h
@@ -402,8 +402,6 @@ void hfp_release_audio_connection(hfp_connection_t * context);
 const char * hfp_hf_feature(int index);
 const char * hfp_ag_feature(int index);
 
-int send_str_over_rfcomm(uint16_t cid, char * command);
-
 #if defined __cplusplus
 }
 #endif
diff --git a/src/hsp_ag.c b/src/hsp_ag.c
index ea51080f0..60e9a106e 100644
--- a/src/hsp_ag.c
+++ b/src/hsp_ag.c
@@ -206,7 +206,7 @@ void hsp_ag_create_service(uint8_t * service, int rfcomm_channel_nr, const char
     }
 }
 
-int send_str_over_rfcomm(uint16_t cid, char * command){
+static int hsp_ag_send_str_over_rfcomm(uint16_t cid, char * command){
     if (!rfcomm_can_send_packet_now(rfcomm_cid)) return 1;
     int err = rfcomm_send_internal(cid, (uint8_t*) command, strlen(command));
     if (err){
@@ -223,7 +223,7 @@ void hsp_ag_support_custom_commands(int enable){
 
 int hsp_ag_send_result(char * result){
     if (!ag_support_custom_commands) return 1;
-    return send_str_over_rfcomm(rfcomm_cid, result);
+    return hsp_ag_send_str_over_rfcomm(rfcomm_cid, result);
 }
 
 
@@ -337,7 +337,7 @@ static void hsp_run(void){
     int err;
 
     if (ag_send_ok){
-        err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
+        err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
         if (!err){
             ag_send_ok = 0;  
         } 
@@ -345,7 +345,7 @@ static void hsp_run(void){
     }
 
     if (ag_send_error){
-        err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
+        err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_ERROR);
         if (!err) ag_send_error = 0;
         return;
     }
@@ -359,14 +359,14 @@ static void hsp_run(void){
 
         case HSP_W4_RING_ANSWER:
             if (ag_ring){
-                err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
+                err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_RING);
                 if (!err) ag_ring = 0;
                 break;
             }
 
             if (!ag_num_button_press_received) break;    
             
-            err = send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
+            err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, HSP_AG_OK);
             if (!err) {
                 hsp_state = HSP_W2_CONNECT_SCO;
                 ag_send_ok = 0;
@@ -395,7 +395,7 @@ static void hsp_run(void){
             if (ag_microphone_gain >= 0){
                 char buffer[10];
                 sprintf(buffer, "%s=%d\r\n", HSP_MICROPHONE_GAIN, ag_microphone_gain);
-                err = send_str_over_rfcomm(rfcomm_cid, buffer);
+                err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
                 if (!err) ag_microphone_gain = -1;
                 break;
             }
@@ -403,7 +403,7 @@ static void hsp_run(void){
             if (ag_speaker_gain >= 0){
                 char buffer[10];
                 sprintf(buffer, "%s=%d\r\n", HSP_SPEAKER_GAIN, ag_speaker_gain);
-                err = send_str_over_rfcomm(rfcomm_cid, buffer);
+                err = hsp_ag_send_str_over_rfcomm(rfcomm_cid, buffer);
                 if (!err) ag_speaker_gain = -1;
                 break;
             }
diff --git a/src/hsp_hs.c b/src/hsp_hs.c
index ec8cd4b6b..e493f354f 100644
--- a/src/hsp_hs.c
+++ b/src/hsp_hs.c
@@ -137,7 +137,7 @@ static void emit_event(uint8_t event_subtype, uint8_t value){
 // remote audio volume control
 // AG +VGM=13 [0..15] ; HS AT+VGM=6 | AG OK
 
-int send_str_over_rfcomm(uint16_t cid, char * command){
+static int hsp_hs_send_str_over_rfcomm(uint16_t cid, char * command){
     if (!rfcomm_can_send_packet_now(rfcomm_cid)) return 1;
     int err = rfcomm_send_internal(cid, (uint8_t*) command, strlen(command));
     if (err){
@@ -155,7 +155,7 @@ void hsp_hs_support_custom_indications(int enable){
 // by calling hsp_hs_send_result function.
 int hsp_hs_send_result(char * result){
     if (!hs_support_custom_indications) return 1;
-    return send_str_over_rfcomm(rfcomm_cid, result);
+    return hsp_hs_send_str_over_rfcomm(rfcomm_cid, result);
 }
 
 
@@ -319,9 +319,9 @@ static void hsp_run(void){
             
     if (hs_send_button_press){
         if (hsp_state == HSP_W4_USER_ACTION){
-            err = send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
+            err = hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_AT_CKPD);
         } else {
-            err = send_str_over_rfcomm(rfcomm_cid, HSP_HS_BUTTON_PRESS);
+            err = hsp_hs_send_str_over_rfcomm(rfcomm_cid, HSP_HS_BUTTON_PRESS);
         }
         if (!err) hs_send_button_press = 0;
         return;
@@ -347,7 +347,7 @@ static void hsp_run(void){
              if (hs_microphone_gain >= 0){
                 char buffer[20];
                 sprintf(buffer, "%s=%d\r\n", HSP_HS_MICROPHONE_GAIN, hs_microphone_gain);
-                err = send_str_over_rfcomm(rfcomm_cid, buffer);
+                err = hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
                 if (!err) hs_microphone_gain = -1;
                 break;
             }
@@ -355,7 +355,7 @@ static void hsp_run(void){
             if (hs_speaker_gain >= 0){
                 char buffer[20];
                 sprintf(buffer, "%s=%d\r\n", HSP_HS_SPEAKER_GAIN, hs_speaker_gain);
-                err = send_str_over_rfcomm(rfcomm_cid, buffer);
+                err = hsp_hs_send_str_over_rfcomm(rfcomm_cid, buffer);
                 if (!err) hs_speaker_gain = -1;
                 break;
             }