diff --git a/meshtastic/__main__.py b/meshtastic/__main__.py
index 2870556..9aeef2e 100644
--- a/meshtastic/__main__.py
+++ b/meshtastic/__main__.py
@@ -130,7 +130,7 @@ def getPref(node, comp_name) -> bool:
         return False
 
     # Check if we need to request the config
-    if len(config.ListFields()) != 0:
+    if len(config.ListFields()) != 0 and not isinstance(pref, str): # if str, it's still the empty string, I think
         # read the value
         config_values = getattr(config, config_type.name)
         if not wholeField:
diff --git a/meshtastic/ble_interface.py b/meshtastic/ble_interface.py
index f020979..76e5dc3 100644
--- a/meshtastic/ble_interface.py
+++ b/meshtastic/ble_interface.py
@@ -174,6 +174,10 @@ class BLEInterface(MeshInterface):
                 self.should_read = False
                 retries: int = 0
                 while self._want_receive:
+                    if self.client is None:
+                        logging.debug(f"BLE client is None, shutting down")
+                        self._want_receive = False
+                        continue
                     try:
                         b = bytes(self.client.read_gatt_char(FROMRADIO_UUID))
                     except BleakDBusError as e:
diff --git a/meshtastic/mt_config.py b/meshtastic/mt_config.py
index 662a10d..3b40294 100644
--- a/meshtastic/mt_config.py
+++ b/meshtastic/mt_config.py
@@ -13,6 +13,8 @@ with rather more easily once the code is simplified by this change.
 
 """
 
+from typing import Any, Optional
+
 def reset():
     """
     Restore the namespace to pristine condition.
@@ -33,5 +35,5 @@ args = None
 parser = None
 channel_index = None
 logfile = None
-tunnelInstance = None
+tunnelInstance: Optional[Any] = None
 camel_case = False
diff --git a/meshtastic/stream_interface.py b/meshtastic/stream_interface.py
index abaef4a..c1fecab 100644
--- a/meshtastic/stream_interface.py
+++ b/meshtastic/stream_interface.py
@@ -38,6 +38,7 @@ class StreamInterface(MeshInterface):
             raise Exception( # pylint: disable=W0719
                 "StreamInterface is now abstract (to update existing code create SerialInterface instead)"
             )
+        self.stream: Optional[serial.Serial] # only serial uses this, TCPInterface overrides the relevant methods instead
         self._rxBuf = bytes()  # empty
         self._wantExit = False
 
@@ -115,7 +116,7 @@ class StreamInterface(MeshInterface):
         bufLen: int = len(b)
         # We convert into a string, because the TCP code doesn't work with byte arrays
         header: bytes = bytes([START1, START2, (bufLen >> 8) & 0xFF, bufLen & 0xFF])
-        logging.debug(f"sending header:{header} b:{b}")
+        logging.debug(f"sending header:{header!r} b:{b!r}")
         self._writeBytes(header + b)
 
     def close(self) -> None:
diff --git a/meshtastic/util.py b/meshtastic/util.py
index 2490660..2e0a989 100644
--- a/meshtastic/util.py
+++ b/meshtastic/util.py
@@ -369,13 +369,12 @@ def readnet_u16(p, offset: int) -> int:
     return p[offset] * 256 + p[offset + 1]
 
 
-def convert_mac_addr(val: bytes) -> Union[str, bytes]:
+def convert_mac_addr(val: str) -> Union[str, bytes]:
     """Convert the base 64 encoded value to a mac address
     val - base64 encoded value (ex: '/c0gFyhb'))
     returns: a string formatted like a mac address (ex: 'fd:cd:20:17:28:5b')
     """
-    if not re.match("[0-9a-f]{2}([-:]?)[0-9a-f]{2}(\\1[0-9a-f]{2}){4}$", val):	#FIXME - does the regex have to be bytes too to
-                                                                                #match val since val is bytes?
+    if not re.match("[0-9a-f]{2}([-:]?)[0-9a-f]{2}(\\1[0-9a-f]{2}){4}$", val):
         val_as_bytes: bytes = base64.b64decode(val)
         return hexstr(val_as_bytes)
     return val
@@ -656,6 +655,8 @@ def check_if_newer_version() -> Optional[str]:
         pass
     act_version = get_active_version()
 
+    if pypi_version is None:
+        return None
     try:
         parsed_act_version = pkg_version.parse(act_version)
         parsed_pypi_version = pkg_version.parse(pypi_version)