diff --git a/test/test_helper.exs b/test/test_helper.exs
index 7db213e5..fe115e04 100644
--- a/test/test_helper.exs
+++ b/test/test_helper.exs
@@ -4,4 +4,16 @@ ExUnit.start(capture_log: true)
 Sandbox.mode(Microwaveprop.Repo, :manual)
 Sandbox.mode(Microwaveprop.AprsRepo, :manual)
 
+# Silence sandbox-cleanup disconnect noise. When a test process exits
+# while still owning a Postgrex connection, the protocol logs an
+# `[error] Postgrex.Protocol ... disconnected: ... client #PID<...>
+# exited`. It's benign — the connection is being torn down on purpose
+# — but at :error level it bypasses `capture_log: true` (which only
+# captures logs from the test process). Pinning these modules to
+# :critical drops the noise without affecting real DB error logging.
+Logger.put_module_level(
+  [Postgrex.Protocol, DBConnection.Connection],
+  :critical
+)
+
 Mox.defmock(Microwaveprop.Valkey.MockAdapter, for: Microwaveprop.Valkey.Adapter)