diff --git a/RNS/Identity.py b/RNS/Identity.py
index 15255ca..cee77f9 100644
--- a/RNS/Identity.py
+++ b/RNS/Identity.py
@@ -431,33 +431,39 @@ class Identity:
     def _clean_ratchets():
         RNS.log("Cleaning ratchets...", RNS.LOG_DEBUG)
         try:
+            count = 0
+            removed = 0
+            not_known = 0
             now = time.time()
             ratchetdir = RNS.Reticulum.storagepath+"/ratchets"
             if os.path.isdir(ratchetdir):
                 for filename in os.listdir(ratchetdir):
+                    count += 1
                     try:
                         expired = False
                         corrupted = False
                         with open(f"{ratchetdir}/{filename}", "rb") as rf:
-                            # TODO: Remove individual ratchet file if corrupt
                             try:
                                 ratchet_data = umsgpack.unpackb(rf.read())
-                                if now > ratchet_data["received"]+Identity.RATCHET_EXPIRY:
-                                    expired = True
+                                if now > ratchet_data["received"]+Identity.RATCHET_EXPIRY: expired = True
 
                             except Exception as e:
                                 RNS.log(f"Corrupted ratchet data while reading {ratchetdir}/{filename}, removing file", RNS.LOG_ERROR)
                                 corrupted = True
 
+                        destination_hash = bytes.fromhex(filename)
+                        if not destination_hash in RNS.Identity.known_destinations: unknown = True; not_known += 1
+                        else:                                                       unknown = False
+
                         if expired or corrupted:
                             os.unlink(f"{ratchetdir}/{filename}")
+                            removed += 1
 
                     except Exception as e:
                         RNS.log(f"An error occurred while cleaning ratchets, in the processing of {ratchetdir}/{filename}.", RNS.LOG_ERROR)
                         RNS.log(f"The contained exception was: {e}", RNS.LOG_ERROR)
 
-        except Exception as e:
-            RNS.log(f"An error occurred while cleaning ratchets. The contained exception was: {e}", RNS.LOG_ERROR)
+        except Exception as e: RNS.log(f"An error occurred while cleaning ratchets. The contained exception was: {e}", RNS.LOG_ERROR)
 
     @staticmethod
     def get_ratchet(destination_hash):
diff --git a/RNS/Reticulum.py b/RNS/Reticulum.py
index a38e11e..43d9c0b 100755
--- a/RNS/Reticulum.py
+++ b/RNS/Reticulum.py
@@ -325,6 +325,7 @@ class Reticulum:
         RNS.log(f"Configuration loaded from {self.configpath}", RNS.LOG_VERBOSE)
 
         RNS.Identity.load_known_destinations()
+        if not self.is_connected_to_shared_instance: RNS.Identity._clean_ratchets()
         RNS.Transport.start(self)
 
         if self.use_af_unix:
@@ -354,7 +355,6 @@ class Reticulum:
 
     def __start_jobs(self):
         if self.jobs_thread == None:
-            RNS.Identity._clean_ratchets()
             self.jobs_thread = threading.Thread(target=self.__jobs)
             self.jobs_thread.daemon = True
             self.jobs_thread.start()
diff --git a/RNS/Transport.py b/RNS/Transport.py
index b24d4e1..dce090e 100755
--- a/RNS/Transport.py
+++ b/RNS/Transport.py
@@ -95,6 +95,7 @@ class Transport:
     MAX_RATE_TIMESTAMPS         = 16           # Maximum number of announce timestamps to keep per destination
     PERSIST_RANDOM_BLOBS        = 32           # Maximum number of random blobs per destination to persist to disk
     MAX_RANDOM_BLOBS            = 64           # Maximum number of random blobs per destination to keep in memory
+    READY_WAIT                  = 60           # Maximum wait time for inbound packets received before transport core was ready
 
     interfaces                  = []           # All active interfaces
     destinations                = []           # All active destinations
@@ -166,6 +167,7 @@ class Transport:
 
     pending_local_path_requests = {}
 
+    ready                       = False
     start_time                  = None
     hashlist_maxsize            = 1000000
     job_interval                = 0.250
@@ -400,6 +402,7 @@ class Transport:
 
         # Sort interfaces according to bitrate
         Transport.prioritize_interfaces()
+        Transport.ready = True
 
         # Synthesize tunnels for any interfaces wanting it
         for interface in Transport.interfaces:
@@ -910,7 +913,9 @@ class Transport:
                 if time.time() > Transport.interface_last_jobs + Transport.interface_jobs_interval:
                     Transport.prioritize_interfaces()
                     try:
-                        for interface in Transport.interfaces: interface.process_held_announces()
+                        for interface in Transport.interfaces:
+                            interface.process_held_announces()
+                            if interface.phy_keepalive: interface.send_keepalive()
                         Transport.interface_last_jobs = time.time()
                     except Exception as e:
                         RNS.log(f"Error while processing held per-interface announces: {e}", RNS.LOG_WARNING)
@@ -1320,6 +1325,14 @@ class Transport:
 
     @staticmethod
     def inbound(raw, interface=None):
+        if not Transport.ready:
+            wait_start = time.time()
+            while not Transport.ready:
+                time.sleep(0.25)
+                if time.time() > wait_start + Transport.READY_WAIT:
+                    RNS.log("Inbound packet timed out waiting for transport startup, dropping", RNS.LOG_WARNING)
+                    return
+
         # If interface access codes are enabled,
         # we must authenticate each packet.
         if len(raw) > 2: