diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 3f9c584..015997f 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -10,8 +10,6 @@ jobs:
     with:
       CODE_FOLDER: zigpy_znp
       CACHE_VERSION: 2
-      PRE_COMMIT_CACHE_PATH:  ~/.cache/pre-commit
-      PYTHON_VERSION_DEFAULT: 3.9.15
       MINIMUM_COVERAGE_PERCENTAGE: 95
     secrets:
       CODECOV_TOKEN: ${{ secrets.CODECOV_TOKEN }}
diff --git a/tests/application/test_requests.py b/tests/application/test_requests.py
index 4c7e4dc..2c49361 100644
--- a/tests/application/test_requests.py
+++ b/tests/application/test_requests.py
@@ -294,7 +294,7 @@ async def callback(req):
             nonlocal in_flight_requests
             nonlocal did_lock
 
-            if app._concurrent_requests_semaphore.locked():
+            if app._concurrent_requests_semaphore.locked(priority=0):
                 did_lock = True
 
             in_flight_requests += 1
diff --git a/tests/application/test_startup.py b/tests/application/test_startup.py
index d3098ff..54b551b 100644
--- a/tests/application/test_startup.py
+++ b/tests/application/test_startup.py
@@ -304,7 +304,7 @@ async def test_reset_network_info(device, make_application):
     "device, concurrency",
     [
         (FormedLaunchpadCC26X2R1, 16),
-        (FormedZStack1CC2531, 2),
+        (FormedZStack1CC2531, 4),
     ],
 )
 async def test_concurrency_auto_config(device, concurrency, make_application):
@@ -312,4 +312,4 @@ async def test_concurrency_auto_config(device, concurrency, make_application):
     await app.connect()
     await app.start_network()
 
-    assert app._concurrent_requests_semaphore.max_value == concurrency
+    assert app._concurrent_requests_semaphore.max_concurrency == concurrency
diff --git a/tests/conftest.py b/tests/conftest.py
index 059981b..0a15190 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -154,7 +154,7 @@ def passthrough_serial_conn(loop, protocol_factory, url, *args, **kwargs):
             return fut
 
         mocker.patch(
-            "serial_asyncio.create_serial_connection", new=passthrough_serial_conn
+            "serial_asyncio_fast.create_serial_connection", new=passthrough_serial_conn
         )
 
         # So we don't have to import it every time
diff --git a/tests/test_uart.py b/tests/test_uart.py
index 80efbb1..d16c5af 100644
--- a/tests/test_uart.py
+++ b/tests/test_uart.py
@@ -1,7 +1,7 @@
 import asyncio
 
 import pytest
-from serial_asyncio import SerialTransport
+from serial_asyncio_fast import SerialTransport
 
 import zigpy_znp.types as t
 import zigpy_znp.config as conf
@@ -47,7 +47,7 @@ def create_serial_conn(loop, protocol_factory, url, *args, **kwargs):
 
         return fut
 
-    mocker.patch("serial_asyncio.create_serial_connection", new=create_serial_conn)
+    mocker.patch("serial_asyncio_fast.create_serial_connection", new=create_serial_conn)
 
     return device, serial_interface
 
diff --git a/zigpy_znp/zigbee/application.py b/zigpy_znp/zigbee/application.py
index 06984a3..a9e2ce1 100644
--- a/zigpy_znp/zigbee/application.py
+++ b/zigpy_znp/zigbee/application.py
@@ -187,12 +187,12 @@ async def start_network(self, *, read_only=False):
             None,
             zigpy.config.defaults.CONF_MAX_CONCURRENT_REQUESTS_DEFAULT,
         ):
-            max_concurrent_requests = 16 if self._znp.nvram.align_structs else 2
+            max_concurrent_requests = 16 if self._znp.nvram.align_structs else 4
         else:
             max_concurrent_requests = self._config[conf.CONF_MAX_CONCURRENT_REQUESTS]
 
         # Update the max value of the concurrent request semaphore at runtime
-        self._concurrent_requests_semaphore.max_value = max_concurrent_requests
+        self._concurrent_requests_semaphore.max_concurrency = max_concurrent_requests
 
         if self.state.network_info.network_key.key == const.Z2M_NETWORK_KEY:
             LOGGER.warning(
diff --git a/zigpy_znp/znp/security.py b/zigpy_znp/znp/security.py
index acc8ce5..fcbcf11 100644
--- a/zigpy_znp/znp/security.py
+++ b/zigpy_znp/znp/security.py
@@ -296,7 +296,7 @@ async def read_devices(
 
     async for key in read_hashed_link_keys(znp, tclk_seed):
         if key.partner_ieee not in devices:
-            LOGGER.warning(
+            LOGGER.debug(
                 "Skipping hashed link key %s (tx: %s, rx: %s) for unknown device %s",
                 ":".join(f"{b:02x}" for b in key.key),
                 key.tx_counter,
@@ -309,7 +309,7 @@ async def read_devices(
 
     async for key in read_unhashed_link_keys(znp, addr_mgr):
         if key.partner_ieee not in devices:
-            LOGGER.warning(
+            LOGGER.debug(
                 "Skipping unhashed link key %s (tx: %s, rx: %s) for unknown device %s",
                 ":".join(f"{b:02x}" for b in key.key),
                 key.tx_counter,