diff --git a/commands.go b/commands.go
index a826461..cd5ee21 100644
--- a/commands.go
+++ b/commands.go
@@ -2,13 +2,14 @@ package gobaresip
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"strconv"
 	"strings"
 	"sync/atomic"
 	"time"
 	"unicode"
+
+	"github.com/goccy/go-json"
 )
 
 /*
diff --git a/go.mod b/go.mod
index 6a044f2..b328219 100644
--- a/go.mod
+++ b/go.mod
@@ -2,4 +2,7 @@ module github.com/negbie/go-baresip
 
 go 1.16
 
-require github.com/gorilla/websocket v1.4.2
+require (
+	github.com/goccy/go-json v0.6.1
+	github.com/gorilla/websocket v1.4.2
+)
diff --git a/go.sum b/go.sum
index 85efffd..d48fae7 100644
--- a/go.sum
+++ b/go.sum
@@ -1,2 +1,4 @@
+github.com/goccy/go-json v0.6.1 h1:O7xC9WR7B09imThbRIEMIWK4MVcxOsLzWtGe16cv5SU=
+github.com/goccy/go-json v0.6.1/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
 github.com/gorilla/websocket v1.4.2 h1:+/TMaTYc4QFitKJxsQ7Yye35DkWvkdLcvGKqM+x0Ufc=
 github.com/gorilla/websocket v1.4.2/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
diff --git a/gobaresip.go b/gobaresip.go
index 80e3614..d72b379 100644
--- a/gobaresip.go
+++ b/gobaresip.go
@@ -68,7 +68,6 @@ int mainLoop(){
 import "C"
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"log"
 	"net"
@@ -79,6 +78,8 @@ import (
 	"sync/atomic"
 	"time"
 	"unsafe"
+
+	"github.com/goccy/go-json"
 )
 
 //ResponseMsg
@@ -221,7 +222,7 @@ func (b *Baresip) read() {
 			b.eventChan <- e
 			if b.wsAddr != "" {
 				select {
-				case b.eventWsChan <- appendByte(e.RawJSON, []byte("\n")):
+				case b.eventWsChan <- e.RawJSON:
 				default:
 				}
 			}
@@ -271,7 +272,7 @@ func (b *Baresip) read() {
 			b.responseChan <- r
 			if b.wsAddr != "" {
 				select {
-				case b.responseWsChan <- appendByte(r.RawJSON, []byte("\n")):
+				case b.responseWsChan <- r.RawJSON:
 				default:
 				}
 			}
@@ -279,13 +280,6 @@ func (b *Baresip) read() {
 	}
 }
 
-func appendByte(prefix []byte, suffix []byte) []byte {
-	b := make([]byte, len(prefix)+len(suffix))
-	n := copy(b, prefix)
-	copy(b[n:], suffix)
-	return b
-}
-
 func findID(data []byte) string {
 	if posA := bytes.Index(data, []byte("call id: ")); posA > 0 {
 		if posB := bytes.Index(data[posA:], []byte("\n")); posB > 0 {
diff --git a/libbaresip/baresip/include/baresip.h b/libbaresip/baresip/include/baresip.h
index 4e457be..5e75ee9 100644
--- a/libbaresip/baresip/include/baresip.h
+++ b/libbaresip/baresip/include/baresip.h
@@ -129,6 +129,8 @@ const char *account_call_transfer(const struct account *acc);
 const char *account_extra(const struct account *acc);
 int account_uri_complete(const struct account *acc, struct mbuf *buf,
 			 const char *uri);
+int account_answerdelay(const struct account *acc);
+void account_set_answerdelay(struct account *acc, int adelay);
 bool account_sip_autoanswer(const struct account *acc);
 void account_set_sip_autoanswer(struct account *acc, bool allow);
 enum sipansbeep account_sipansbeep(const struct account *acc);
diff --git a/libbaresip/baresip/libbaresip.a b/libbaresip/baresip/libbaresip.a
index 47f1dd2..7b9315b 100644
Binary files a/libbaresip/baresip/libbaresip.a and b/libbaresip/baresip/libbaresip.a differ
diff --git a/libbaresip/openssl/libcrypto.a b/libbaresip/openssl/libcrypto.a
index cebfb73..80738f6 100644
Binary files a/libbaresip/openssl/libcrypto.a and b/libbaresip/openssl/libcrypto.a differ
diff --git a/libbaresip/rem/include/rem_au.h b/libbaresip/rem/include/rem_au.h
index 50355c8..1256647 100644
--- a/libbaresip/rem/include/rem_au.h
+++ b/libbaresip/rem/include/rem_au.h
@@ -12,6 +12,7 @@ enum aufmt {
 	AUFMT_PCMU,   /**< G.711 U-law       */
 	AUFMT_FLOAT,  /**< Float 32 bit (CPU endian)                   */
 	AUFMT_S24_3LE,/**< Signed 24bit Little Endian in 3bytes format */
+	AUFMT_RAW,    /**< RAW PCM                                     */
 };
 
 size_t      aufmt_sample_size(enum aufmt fmt);
diff --git a/libbaresip/rem/include/rem_auframe.h b/libbaresip/rem/include/rem_auframe.h
index e9f4f5f..ef1a8ee 100644
--- a/libbaresip/rem/include/rem_auframe.h
+++ b/libbaresip/rem/include/rem_auframe.h
@@ -6,7 +6,7 @@
  * Defines a frame of audio samples
  */
 struct auframe {
-	int fmt;             /**< Sample format (enum aufmt)        */
+	enum aufmt fmt;      /**< Sample format (enum aufmt)        */
 	void *sampv;         /**< Audio samples (must be mem_ref'd) */
 	size_t sampc;        /**< Total number of audio samples     */
 	uint64_t timestamp;  /**< Timestamp in AUDIO_TIMEBASE units */
@@ -14,7 +14,7 @@ struct auframe {
 	uint8_t ch;          /**< Channels                          */
 };
 
-void auframe_init(struct auframe *af, int fmt, void *sampv, size_t sampc,
-		  uint32_t srate, uint8_t ch);
+void auframe_init(struct auframe *af, enum aufmt fmt, void *sampv,
+		  size_t sampc, uint32_t srate, uint8_t ch);
 size_t auframe_size(const struct auframe *af);
 void   auframe_mute(struct auframe *af);
diff --git a/libbaresip/rem/librem.a b/libbaresip/rem/librem.a
index 491d0c5..4bd8455 100644
Binary files a/libbaresip/rem/librem.a and b/libbaresip/rem/librem.a differ
diff --git a/ws.go b/ws.go
index c402cc2..915ee1f 100644
--- a/ws.go
+++ b/ws.go
@@ -23,6 +23,10 @@ const (
 	maxMessageSize = 1024
 )
 
+var (
+	newline = []byte{'\n'}
+)
+
 var upgrader = websocket.Upgrader{
 	ReadBufferSize:  1024,
 	WriteBufferSize: 1024,
@@ -94,6 +98,7 @@ func (c *client) writePump() {
 			// Add queued messages to the current websocket message.
 			n := len(c.send)
 			for i := 0; i < n; i++ {
+				w.Write(newline)
 				w.Write(<-c.send)
 			}