diff --git a/app/src/gen3/connection_g3.py b/app/src/gen3/connection_g3.py
index 66683fa..5aea231 100644
--- a/app/src/gen3/connection_g3.py
+++ b/app/src/gen3/connection_g3.py
@@ -25,10 +25,10 @@ class ConnectionG3(AsyncStream, Talent):
         # logger.info(f'AsyncStream refs: {gc.get_referrers(self)}')
 
     async def async_create_remote(self) -> None:
-        pass  # virtual interface
+        pass  # virtual interface # pragma: no cover
 
     async def async_publ_mqtt(self) -> None:
-        pass  # virtual interface
+        pass  # virtual interface # pragma: no cover
 
     def healthy(self) -> bool:
         logger.debug('ConnectionG3 healthy()')
diff --git a/app/src/gen3plus/connection_g3p.py b/app/src/gen3plus/connection_g3p.py
index dc4eca1..89dfc1a 100644
--- a/app/src/gen3plus/connection_g3p.py
+++ b/app/src/gen3plus/connection_g3p.py
@@ -31,10 +31,10 @@ class ConnectionG3P(AsyncStream, SolarmanV5):
         #  logger.info(f'AsyncStream refs: {gc.get_referrers(self)}')
 
     async def async_create_remote(self) -> None:
-        pass  # virtual interface
+        pass  # virtual interface # pragma: no cover
 
     async def async_publ_mqtt(self) -> None:
-        pass  # virtual interface
+        pass  # virtual interface # pragma: no cover
 
     def healthy(self) -> bool:
         logger.debug('ConnectionG3P healthy()')
diff --git a/app/tests/test_modbus_tcp.py b/app/tests/test_modbus_tcp.py
index c2ed8a2..52aabee 100644
--- a/app/tests/test_modbus_tcp.py
+++ b/app/tests/test_modbus_tcp.py
@@ -110,7 +110,7 @@ class FakeWriter():
 @pytest.fixture
 def patch_open():
     async def new_conn(conn):
-        await asyncio.sleep(0.01)
+        await asyncio.sleep(0)
         return FakeReader(), FakeWriter()
     
     def new_open(host: str, port: int):
@@ -161,12 +161,12 @@ async def test_modbus_cnf1(config_conn, patch_open):
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
     loop = asyncio.get_event_loop()
     ModbusTcp(loop)
-    await asyncio.sleep(0.1)
+    await asyncio.sleep(0.01)
     for m in Message:
         if (m.node_id == 'inv_2'):
             assert False
         
-    await asyncio.sleep(0.1)
+    await asyncio.sleep(0.01)
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
 
 @pytest.mark.asyncio
@@ -181,7 +181,7 @@ async def test_modbus_cnf2(config_conn, patch_no_mqtt, patch_open):
 
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
     ModbusTcp(asyncio.get_event_loop())
-    await asyncio.sleep(0.1)
+    await asyncio.sleep(0.01)
     test = 0
     for m in Message:
         if (m.node_id == 'inv_2'):
@@ -192,7 +192,7 @@ async def test_modbus_cnf2(config_conn, patch_no_mqtt, patch_open):
             del m
         
     assert 1 == test
-    await asyncio.sleep(0.1)
+    await asyncio.sleep(0.01)
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
     # check that the connection is released
     for m in Message:
@@ -211,32 +211,24 @@ async def test_modbus_cnf3(config_conn, patch_no_mqtt, patch_open):
     test = TestType.RD_TEST_0_BYTES
 
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
-    ModbusTcp(asyncio.get_event_loop(), tim_restart= 0.1)
-    await asyncio.sleep(0.1)
+    ModbusTcp(asyncio.get_event_loop(), tim_restart= 0)
+    await asyncio.sleep(0.01)
     test = 0
     for m in Message:
         if (m.node_id == 'inv_2'):
             assert Infos.stat['proxy']['Inverter_Cnt'] == 1
-            m.shutdown_started = False
-            m.reader.on_recv.set()
             test += 1
-            await asyncio.sleep(0.1)
-            assert m.state == State.closed
-    
-    assert 1 == test
-    await asyncio.sleep(0.1)
-    assert Infos.stat['proxy']['Inverter_Cnt'] == 1
-    # check that the connection is released
-    for m in Message:
-        if (m.node_id == 'inv_2'):
-            test += 1
-            m.shutdown_started = True
-            m.reader.on_recv.set()
-            del m
+            if test == 1:
+                m.shutdown_started = False
+                m.reader.on_recv.set()
+                await asyncio.sleep(0.1)
+                assert m.state == State.closed
+                await asyncio.sleep(0.1)
+            else:
+                m.shutdown_started = True
+                m.reader.on_recv.set()
+                del m
 
-    assert 3 == test
-    await asyncio.sleep(0.1)
+    assert 2 == test
+    await asyncio.sleep(0.01)
     assert Infos.stat['proxy']['Inverter_Cnt'] == 0
-    for m in Message:
-        if (m.node_id == 'inv_2'):
-            assert False
diff --git a/app/tests/test_mqtt.py b/app/tests/test_mqtt.py
index 1d7c5dd..3072627 100644
--- a/app/tests/test_mqtt.py
+++ b/app/tests/test_mqtt.py
@@ -97,7 +97,7 @@ async def test_mqtt_no_config(config_no_conn):
     try:
         m = Mqtt(cb)
         assert m.task
-        await asyncio.sleep(1)
+        await asyncio.sleep(0)
         assert not on_connect.is_set()
         try:
             await m.publish('homeassistant/status', 'online')