diff --git a/Cargo.lock b/Cargo.lock
index 45aeeaf5c..66c6e6311 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -9706,8 +9706,7 @@ dependencies = [
 [[package]]
 name = "webrtc-sctp"
 version = "0.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "07439c134425d51d2f10907aaf2f815fdfb587dce19fe94a4ae8b5faf2aae5ae"
+source = "git+https://github.com/rustdesk-org/webrtc?rev=56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833#56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833"
 dependencies = [
  "arc-swap",
  "async-trait",
@@ -9747,7 +9746,7 @@ dependencies = [
 [[package]]
 name = "webrtc-util"
 version = "0.11.0"
-source = "git+https://github.com/rustdesk-org/webrtc?rev=ac9e74ec2dc502d9afce8d5fc3c9644f2139aee7#ac9e74ec2dc502d9afce8d5fc3c9644f2139aee7"
+source = "git+https://github.com/rustdesk-org/webrtc?rev=56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833#56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833"
 dependencies = [
  "async-trait",
  "bitflags 1.3.2",
diff --git a/Cargo.toml b/Cargo.toml
index dca4e6b9c..73771f2c8 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -215,10 +215,15 @@ exclude = ["vdi/host"]
 # This allows building and running on systems without libxdo installed (e.g., Wayland-only)
 [patch.crates-io]
 libxdo-sys = { path = "libs/libxdo-sys-stub" }
-# webrtc-util reads the Windows adapter list's IPv6 addresses as host-order u16 groups, so every
+# One branch off upstream v0.13.0, the tag whose crate versions match this stack.
+# webrtc-util: reads the Windows adapter list's IPv6 addresses as host-order u16 groups, so every
 # one comes out byte-swapped, fails to bind, and ICE gathers no IPv6 host candidate on Windows.
+# webrtc-sctp: RFC 4960's 1s RTO floor makes a single loss cost 1-3s on a link whose RTT is 24-64ms,
+# and fast retransmit cannot cover a request/response exchange; INITIAL_MTU 1228 also fragments on
+# IPv6. The fork commit carries the arithmetic.
 # Pinned by rev, not branch: a fork branch can be rewritten out from under the lockfile.
-webrtc-util = { git = "https://github.com/rustdesk-org/webrtc", rev = "ac9e74ec2dc502d9afce8d5fc3c9644f2139aee7" }
+webrtc-util = { git = "https://github.com/rustdesk-org/webrtc", rev = "56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833" }
+webrtc-sctp = { git = "https://github.com/rustdesk-org/webrtc", rev = "56d097c54f9ea1e48c0dfbeb6ce7e66d2e66e833" }
 
 [package.metadata.winres]
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