diff -Nru mtxclient-0.9.2.orig/lib/structs/events/voip.cpp mtxclient-0.9.2/lib/structs/events/voip.cpp
--- mtxclient-0.9.2.orig/lib/structs/events/voip.cpp	2023-02-20 01:56:06.000000000 +0100
+++ mtxclient-0.9.2/lib/structs/events/voip.cpp	2023-10-07 14:59:43.056218917 +0200
@@ -8,7 +8,7 @@
 
 namespace {
 std::string
-version(const json &obj)
+m_version(const json &obj)
 {
     auto v = obj.at("version");
     return v.is_number() ? "0" : v.get<std::string>();
@@ -53,7 +53,7 @@
 {
     content.call_id  = obj.at("call_id").get<std::string>();
     content.offer    = obj.at("offer").get<RTCSessionDescriptionInit>();
-    content.version  = version(obj);
+    content.version  = m_version(obj);
     content.lifetime = obj.at("lifetime").get<uint32_t>();
     if (content.version != "0") {
         content.party_id = obj.at("party_id").get<std::string>();
@@ -100,7 +100,7 @@
 {
     content.call_id    = obj.at("call_id").get<std::string>();
     content.candidates = obj.at("candidates").get<std::vector<CallCandidates::Candidate>>();
-    content.version    = version(obj);
+    content.version    = m_version(obj);
     if (content.version != "0") {
         content.party_id = obj.at("party_id").get<std::string>();
     }
@@ -123,7 +123,7 @@
 {
     content.call_id = obj.at("call_id").get<std::string>();
     content.answer  = obj.at("answer").get<RTCSessionDescriptionInit>();
-    content.version = version(obj);
+    content.version = m_version(obj);
     if (content.version != "0") {
         content.party_id = obj.at("party_id").get<std::string>();
     }
@@ -145,7 +145,7 @@
 from_json(const json &obj, CallHangUp &content)
 {
     content.call_id = obj.at("call_id").get<std::string>();
-    content.version = version(obj);
+    content.version = m_version(obj);
     if (content.version != "0") {
         content.party_id = obj.at("party_id").get<std::string>();
     }
@@ -198,7 +198,7 @@
 from_json(const json &obj, CallSelectAnswer &content)
 {
     content.call_id           = obj.at("call_id").get<std::string>();
-    content.version           = version(obj);
+    content.version           = m_version(obj);
     content.party_id          = obj.at("party_id").get<std::string>();
     content.selected_party_id = obj.at("selected_party_id").get<std::string>();
 }
@@ -217,7 +217,7 @@
 from_json(const json &obj, CallReject &content)
 {
     content.call_id  = obj.at("call_id").get<std::string>();
-    content.version  = version(obj);
+    content.version  = m_version(obj);
     content.party_id = obj.at("party_id").get<std::string>();
 }