diff --git a/packages/core/src/network/multi-session-connection.ts b/packages/core/src/network/multi-session-connection.ts
index 07c1a73d..59f1ea96 100644
--- a/packages/core/src/network/multi-session-connection.ts
+++ b/packages/core/src/network/multi-session-connection.ts
@@ -143,6 +143,7 @@ export class MultiSessionConnection {
             })
 
             this._connections.push(conn)
+            if (this._authKey !== null) conn._session._authKey.setup(this._authKey)
             // if enforcePfsChanged, we need to connect after setting the new auth key
             if (connect && !enforcePfsChanged) conn.connect()
         }
@@ -212,10 +213,16 @@ export class MultiSessionConnection {
         this.connect()
     }
 
-    setAuthKey(authKey: Uint8Array | null, temp = false, idx = 0): void {
-        const session = this._connections[idx]._session
-        const key = temp ? session._authKeyTemp : session._authKey
-        key.setup(authKey)
+    private _authKey: Uint8Array | null = null
+    setAuthKey(authKey: Uint8Array | null): void {
+        this._authKey = authKey
+        for (const conn of this._connections) {
+            conn._session._authKey.setup(authKey)
+        }
+    }
+
+    setTempAuthKey(authKey: Uint8Array | null, idx: number): void {
+        this._connections[idx]?._session._authKeyTemp.setup(authKey)
     }
 
     resetAuthKeys(): void {
diff --git a/packages/core/src/network/network-manager.ts b/packages/core/src/network/network-manager.ts
index 1ee74217..d3926aa2 100644
--- a/packages/core/src/network/network-manager.ts
+++ b/packages/core/src/network/network-manager.ts
@@ -314,7 +314,7 @@ export class DcConnectionManager {
         const connection = this[kind]
 
         connection.onKeyChange.add(([idx, key]) => {
-            if (kind !== 'main') {
+            if (kind !== 'main' && key !== null) {
                 // main connection is responsible for authorization,
                 // and keys are then sent to other connections
                 this.manager._log.warn('got key-change from non-main connection, ignoring')
@@ -322,7 +322,7 @@ export class DcConnectionManager {
                 return
             }
 
-            this.manager._log.debug('key change for dc %d from connection %d', this.dcId, idx)
+            this.manager._log.debug('key change (empty=%b) for dc %d from connection %d', key === null, this.dcId, idx)
 
             // send key to other connections
             this.upload.setAuthKey(key)
@@ -433,7 +433,7 @@ export class DcConnectionManager {
             await Promise.all(
                 Array.from({ length: this.main.getCount() }, async (_, i) => {
                     const temp = await this.manager._storage.provider.authKeys.getTemp(this.dcId, i, now)
-                    this.main.setAuthKey(temp, true, i)
+                    this.main.setTempAuthKey(temp, i)
 
                     // NB: we do not set temp auth keys for media connections,
                     // as they are ephemeral and dc-bound. doing this *will* lead to unwanted -404s
diff --git a/packages/core/src/network/session-connection.ts b/packages/core/src/network/session-connection.ts
index f9c73b65..28cdf7d0 100644
--- a/packages/core/src/network/session-connection.ts
+++ b/packages/core/src/network/session-connection.ts
@@ -99,6 +99,8 @@ export class SessionConnection extends PersistentConnection {
     readonly onUpdate: Emitter<tl.TypeUpdates> = new Emitter()
     readonly onFutureSalts: Emitter<mtp.RawMt_future_salt[]> = new Emitter()
 
+    private _triedReconnectingOn404 = false
+
     constructor(params: SessionConnectionParams, log: Logger) {
         super(params, log.create('conn'))
         this._session = new MtprotoSession(
@@ -263,6 +265,14 @@ export class SessionConnection extends PersistentConnection {
                     // otherwise, 404 must be referencing the perm_key
                 }
 
+                if (!this._triedReconnectingOn404) {
+                    // maybe this is some mtproto issue? let's try reconnecting and hope for the best
+                    this.log.warn('transport error 404. trying to reconnect')
+                    this._triedReconnectingOn404 = true
+                    this._resetSession()
+                    return
+                }
+
                 // there happened a little trolling
                 this.log.warn('transport error 404, reauthorizing')
                 this._session.resetAuthKey()
@@ -1176,6 +1186,7 @@ export class SessionConnection extends PersistentConnection {
         }
 
         this._salts.currentSalt = serverSalt
+        this._triedReconnectingOn404 = false
 
         this.log.debug('received new_session_created, uid = %l, first msg_id = %l', uniqueId, firstMsgId)