--- include/asterisk/format_cap.h	(Asterisk 13.38.1)
+++ include/asterisk/format_cap.h	(working copy)
@@ -149,6 +149,20 @@ int ast_format_cap_append_by_type(struct
 int ast_format_cap_append_from_cap(struct ast_format_cap *dst, const struct ast_format_cap *src, enum ast_media_type type);
 
 /*!
+ * \brief Append all formats except of provided type in src to dst
+ *
+ * \param dst The destination capabilities structure
+ * \param src The source capabilities structure
+ * \param type The type of formats not to append.
+ *
+ * \retval 0 success
+ * \retval -1 failure
+ *
+ * \note If AST_MEDIA_TYPE_UNKNOWN is passed as the type all codecs will be removed.
+ */
+int ast_format_cap_append_from_cap_except(struct ast_format_cap *dst, const struct ast_format_cap *src, enum ast_media_type type);
+
+/*!
  * \brief Replace the formats of provided type in dst with equivalent formats from src
  *
  * \param dst The destination capabilities structure
--- main/format_cap.c	(Asterisk 13.38.1)
+++ main/format_cap.c	(working copy)
@@ -320,2 +320,18 @@ int ast_format_cap_append_from_cap(struc
 
+int ast_format_cap_append_from_cap_except(struct ast_format_cap *dst, const struct ast_format_cap *src,
+	enum ast_media_type type)
+{
+	int idx, res = 0;
+
+	for (idx = 0; (idx < AST_VECTOR_SIZE(&src->preference_order)) && !res; ++idx) {
+		struct format_cap_framed *framed = AST_VECTOR_GET(&src->preference_order, idx);
+
+		if (ast_format_get_type(framed->format) != type) {
+			res = ast_format_cap_append(dst, framed->format, framed->framing);
+		}
+	}
+
+	return res;
+}
+
 static int format_cap_replace(struct ast_format_cap *cap, struct ast_format *format, unsigned int framing)
--- main/channel.c	(Asterisk 13.38.1)
+++ main/channel.c	(working copy)
@@ -6419,5 +6419,4 @@ struct ast_channel *ast_request(const ch
 		}
-		ast_format_cap_append_from_cap(joint_cap, request_cap, AST_MEDIA_TYPE_UNKNOWN);
-		ast_format_cap_remove_by_type(joint_cap, AST_MEDIA_TYPE_AUDIO);
 		ast_format_cap_append(joint_cap, best_audio_fmt, 0);
+		ast_format_cap_append_from_cap_except(joint_cap, request_cap, AST_MEDIA_TYPE_AUDIO);