diff --git a/cabal.project b/cabal.project
index f7102312c..b7baee588 100644
--- a/cabal.project
+++ b/cabal.project
@@ -9,7 +9,7 @@ constraints: zip +disable-bzip2 +disable-zstd
 source-repository-package
     type: git
     location: https://github.com/simplex-chat/simplexmq.git
-    tag: e0b7942e45e36d92625e07c0c1ce9ca2375a0980
+    tag: 3b348a463cd83fbd803743b1d67f282a42d8b654
 
 source-repository-package
     type: git
diff --git a/docs/DOWNLOADS.md b/docs/DOWNLOADS.md
index 94b8d9197..a1576c355 100644
--- a/docs/DOWNLOADS.md
+++ b/docs/DOWNLOADS.md
@@ -25,7 +25,7 @@ Using the same profile as on mobile device is not yet supported – you need to
 
 **Mac**: [x86_64](https://github.com/simplex-chat/simplex-chat/releases/download/v5.3.2/simplex-desktop-macos-x86_64.dmg) (Intel), [aarch64](https://github.com/simplex-chat/simplex-chat/releases/download/v5.3.1/simplex-desktop-macos-aarch64.dmg) (Apple Silicon).
 
-**Windows**: [x86_64](https://github.com/simplex-chat/simplex-chat/releases/download/v5.4.0-beta.0/simplex-desktop-windows-x86-64.msi) (BETA).
+**Windows**: [x86_64](https://github.com/simplex-chat/simplex-chat/releases/download/v5.4.0-beta.3/simplex-desktop-windows-x86-64.msi) (BETA).
 
 ## Mobile apps
 
diff --git a/scripts/nix/sha256map.nix b/scripts/nix/sha256map.nix
index d7870a87c..5f6574288 100644
--- a/scripts/nix/sha256map.nix
+++ b/scripts/nix/sha256map.nix
@@ -1,5 +1,5 @@
 {
-  "https://github.com/simplex-chat/simplexmq.git"."e0b7942e45e36d92625e07c0c1ce9ca2375a0980" = "0swbcrmdirwqrk0kx5jmc5lcrzasccfwn3papb5c1p8hn0hjnzj7";
+  "https://github.com/simplex-chat/simplexmq.git"."3b348a463cd83fbd803743b1d67f282a42d8b654" = "1rbd5zz1rclnfvjf68ll5qhi9yqk040bi491z10hwyhxi2bixpaw";
   "https://github.com/simplex-chat/hs-socks.git"."a30cc7a79a08d8108316094f8f2f82a0c5e1ac51" = "0yasvnr7g91k76mjkamvzab2kvlb1g5pspjyjn2fr6v83swjhj38";
   "https://github.com/kazu-yamamoto/http2.git"."f5525b755ff2418e6e6ecc69e877363b0d0bcaeb" = "0fyx0047gvhm99ilp212mmz37j84cwrfnpmssib5dw363fyb88b6";
   "https://github.com/simplex-chat/direct-sqlcipher.git"."f814ee68b16a9447fbb467ccc8f29bdd3546bfd9" = "1ql13f4kfwkbaq7nygkxgw84213i0zm7c1a8hwvramayxl38dq5d";
diff --git a/src/Simplex/Chat.hs b/src/Simplex/Chat.hs
index 8b9abfde5..619f93b89 100644
--- a/src/Simplex/Chat.hs
+++ b/src/Simplex/Chat.hs
@@ -3680,6 +3680,7 @@ processAgentMessageConn user@User {userId} corrId agentConnId agentMessage = do
       RATCHET_HEADER -> (MDERatchetHeader, 1)
       RATCHET_EARLIER _ -> (MDERatchetEarlier, 1)
       RATCHET_SKIPPED n -> (MDETooManySkipped, n)
+      RATCHET_SYNC -> (MDERatchetSync, 0)
 
     mdeUpdatedCI :: (MsgDecryptError, Word32) -> CChatItem c -> Maybe (ChatItem c 'MDRcv, CIContent 'MDRcv)
     mdeUpdatedCI (mde', n') (CChatItem _ ci@ChatItem {content = CIRcvDecryptionError mde n})
@@ -3688,6 +3689,7 @@ processAgentMessageConn user@User {userId} corrId agentConnId agentMessage = do
         MDETooManySkipped -> r n' -- the numbers are not added as sequential MDETooManySkipped will have it incremented by 1
         MDERatchetEarlier -> r (n + n')
         MDEOther -> r (n + n')
+        MDERatchetSync -> r 0
       | otherwise = Nothing
       where
         r n'' = Just (ci, CIRcvDecryptionError mde n'')
diff --git a/src/Simplex/Chat/Messages/CIContent.hs b/src/Simplex/Chat/Messages/CIContent.hs
index bc0e31ebf..8d5e2ddd8 100644
--- a/src/Simplex/Chat/Messages/CIContent.hs
+++ b/src/Simplex/Chat/Messages/CIContent.hs
@@ -151,7 +151,12 @@ ciMsgContent = \case
   CIRcvMsgContent mc -> Just mc
   _ -> Nothing
 
-data MsgDecryptError = MDERatchetHeader | MDETooManySkipped | MDERatchetEarlier | MDEOther
+data MsgDecryptError
+  = MDERatchetHeader
+  | MDETooManySkipped
+  | MDERatchetEarlier
+  | MDEOther
+  | MDERatchetSync
   deriving (Eq, Show)
 
 ciRequiresAttention :: forall d. MsgDirectionI d => CIContent d -> Bool
@@ -322,6 +327,7 @@ msgDecryptErrorText err n =
       MDETooManySkipped -> Just $ "too many skipped messages" <> counter
       MDERatchetEarlier -> Just $ "earlier message" <> counter
       MDEOther -> counter_
+      MDERatchetSync -> Just "synchronization error"
     counter_ = if n == 1 then Nothing else Just $ tshow n <> " messages"
     counter = maybe "" (", " <>) counter_
 
diff --git a/stack.yaml b/stack.yaml
index befe0b60b..4ef1c422e 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -49,7 +49,7 @@ extra-deps:
   # - simplexmq-1.0.0@sha256:34b2004728ae396e3ae449cd090ba7410781e2b3cefc59259915f4ca5daa9ea8,8561
   # - ../simplexmq
   - github: simplex-chat/simplexmq
-    commit: e0b7942e45e36d92625e07c0c1ce9ca2375a0980
+    commit: 3b348a463cd83fbd803743b1d67f282a42d8b654
   - github: kazu-yamamoto/http2
     commit: f5525b755ff2418e6e6ecc69e877363b0d0bcaeb
   # - ../direct-sqlcipher