diff --git a/client/src/app/core/core-services/autoupdate.service.ts b/client/src/app/core/core-services/autoupdate.service.ts
index ceaeda77a..3303d0740 100644
--- a/client/src/app/core/core-services/autoupdate.service.ts
+++ b/client/src/app/core/core-services/autoupdate.service.ts
@@ -3,6 +3,7 @@ import { Injectable } from '@angular/core';
 import { BaseModel } from '../../shared/models/base/base-model';
 import { CollectionStringMapperService } from './collection-string-mapper.service';
 import { DataStoreService, DataStoreUpdateManagerService } from './data-store.service';
+import { Mutex } from '../promises/mutex';
 import { WebsocketService, WEBSOCKET_ERROR_CODES } from './websocket.service';
 
 interface AutoupdateFormat {
@@ -45,6 +46,7 @@ interface AutoupdateFormat {
     providedIn: 'root'
 })
 export class AutoupdateService {
+    private mutex = new Mutex();
     /**
      * Constructor to create the AutoupdateService. Calls the constructor of the parent class.
      * @param websocketService
@@ -79,11 +81,13 @@ export class AutoupdateService {
      * Handles the change ids of all autoupdates.
      */
     private async storeResponse(autoupdate: AutoupdateFormat): Promise<void> {
+        const unlock = await this.mutex.lock();
         if (autoupdate.all_data) {
             await this.storeAllData(autoupdate);
         } else {
             await this.storePartialAutoupdate(autoupdate);
         }
+        unlock();
     }
 
     /**
diff --git a/client/src/app/core/core-services/data-store.service.ts b/client/src/app/core/core-services/data-store.service.ts
index a9ff9fc7e..b9ed07a08 100644
--- a/client/src/app/core/core-services/data-store.service.ts
+++ b/client/src/app/core/core-services/data-store.service.ts
@@ -258,6 +258,7 @@ export class DataStoreUpdateManagerService {
 
     private serveNextSlot(): void {
         if (this.updateSlotRequests.length > 0) {
+            console.warn('Concurrent update slots');
             const request = this.updateSlotRequests.pop();
             request.resolve();
         }
diff --git a/client/src/app/core/promises/mutex.ts b/client/src/app/core/promises/mutex.ts
new file mode 100644
index 000000000..3de879915
--- /dev/null
+++ b/client/src/app/core/promises/mutex.ts
@@ -0,0 +1,30 @@
+/**
+ * A mutex as described in every textbook
+ *
+ * Usage:
+ * ```
+ * mutex = new Mutex(); // create e.g. as class member
+ *
+ * // Somewhere in the code to lock (must be async code!)
+ * const unlock = await this.mutex.lock()
+ * // ...the code to synchronize
+ * unlock()
+ * ```
+ */
+export class Mutex {
+    private mutex = Promise.resolve();
+
+    public lock(): PromiseLike<() => void> {
+        // this will capture the code-to-synchronize
+        let begin: (unlock: () => void) => void = () => {};
+
+        // All "requests" to execute code are chained in a promise-chain
+        this.mutex = this.mutex.then(() => {
+            return new Promise(begin);
+        });
+
+        return new Promise(res => {
+            begin = res;
+        });
+    }
+}
diff --git a/openslides/utils/cache_providers.py b/openslides/utils/cache_providers.py
index 1fb0cc60f..e049a5211 100644
--- a/openslides/utils/cache_providers.py
+++ b/openslides/utils/cache_providers.py
@@ -8,7 +8,11 @@ from django.core.exceptions import ImproperlyConfigured
 from typing_extensions import Protocol
 
 from . import logging
-from .redis import read_only_redis_amount_replicas, use_redis
+from .redis import (
+    read_only_redis_amount_replicas,
+    read_only_redis_wait_timeout,
+    use_redis,
+)
 from .schema_version import SchemaVersion
 from .utils import split_element_id, str_dict_to_bytes
 
@@ -452,11 +456,11 @@ class RedisCacheProvider:
                     raise e
             if not read_only and read_only_redis_amount_replicas is not None:
                 reported_amount = await redis.wait(
-                    read_only_redis_amount_replicas, 1000
+                    read_only_redis_amount_replicas, read_only_redis_wait_timeout
                 )
                 if reported_amount != read_only_redis_amount_replicas:
                     logger.warn(
-                        f"WAIT reported {reported_amount} replicas of {read_only_redis_amount_replicas} requested!"
+                        f"WAIT reported {reported_amount} replicas of {read_only_redis_amount_replicas} requested after {read_only_redis_wait_timeout} ms!"
                     )
             return result
 
diff --git a/openslides/utils/redis.py b/openslides/utils/redis.py
index acc370f54..d5ff24065 100644
--- a/openslides/utils/redis.py
+++ b/openslides/utils/redis.py
@@ -11,6 +11,7 @@ logger = logging.getLogger(__name__)
 use_redis = False
 use_read_only_redis = False
 read_only_redis_amount_replicas = None
+read_only_redis_wait_timeout = None
 
 try:
     import aioredis
@@ -35,6 +36,8 @@ else:
 
             read_only_redis_amount_replicas = getattr(settings, "AMOUNT_REPLICAS", 1)
             logger.info(f"AMOUNT_REPLICAS={read_only_redis_amount_replicas}")
+            read_only_redis_wait_timeout = getattr(settings, "WAIT_TIMEOUT", 1000)
+            logger.info(f"WAIT_TIMEOUT={read_only_redis_wait_timeout}")
     else:
         logger.info("Redis is not configured.")