diff --git a/src/fenrirscreenreader/core/processManager.py b/src/fenrirscreenreader/core/processManager.py
index 5ec18cdb..d6835397 100644
--- a/src/fenrirscreenreader/core/processManager.py
+++ b/src/fenrirscreenreader/core/processManager.py
@@ -13,7 +13,19 @@ from fenrirscreenreader.core import debug
 from fenrirscreenreader.core.eventData import FenrirEventType
 
 
-# Standalone worker functions for multiprocessing (cannot be instance methods)
+# Standalone functions for multiprocessing (cannot be instance methods)
+def _heart_beat_timer(running):
+    """
+    Standalone heartbeat timer function for multiprocessing.
+    Returns current timestamp after a short sleep.
+    """
+    try:
+        time.sleep(0.5)
+    except Exception as e:
+        print(f"ProcessManager _heart_beat_timer: Error during sleep: {e}")
+    return time.time()
+
+
 def _custom_event_worker_process(
     running, event_queue, function, pargs=None, run_once=False
 ):
@@ -81,7 +93,7 @@ class ProcessManager:
         self.running = self.env["runtime"]["EventManager"].get_running()
         self.add_simple_event_thread(
             FenrirEventType.heart_beat,
-            self.heart_beat_timer,
+            _heart_beat_timer,
             multiprocess=True,
         )
 
diff --git a/src/fenrirscreenreader/remoteDriver/tcpDriver.py b/src/fenrirscreenreader/remoteDriver/tcpDriver.py
index 149eda17..dd89ce4a 100644
--- a/src/fenrirscreenreader/remoteDriver/tcpDriver.py
+++ b/src/fenrirscreenreader/remoteDriver/tcpDriver.py
@@ -20,8 +20,10 @@ class driver(remoteDriver):
 
     def initialize(self, environment):
         self.env = environment
+        # Use threading instead of multiprocessing to avoid pickle issues
+        # with self.env (which contains unpicklable file handles)
         self.env["runtime"]["ProcessManager"].add_custom_event_thread(
-            self.watch_dog, multiprocess=True
+            self.watch_dog, multiprocess=False
         )
 
     def watch_dog(self, active, event_queue):
diff --git a/src/fenrirscreenreader/remoteDriver/unixDriver.py b/src/fenrirscreenreader/remoteDriver/unixDriver.py
index d994ecfa..088c7339 100644
--- a/src/fenrirscreenreader/remoteDriver/unixDriver.py
+++ b/src/fenrirscreenreader/remoteDriver/unixDriver.py
@@ -20,8 +20,10 @@ class driver(remoteDriver):
 
     def initialize(self, environment):
         self.env = environment
+        # Use threading instead of multiprocessing to avoid pickle issues
+        # with self.env (which contains unpicklable file handles)
         self.env["runtime"]["ProcessManager"].add_custom_event_thread(
-            self.watch_dog, multiprocess=True
+            self.watch_dog, multiprocess=False
         )
 
     def watch_dog(self, active, event_queue):
diff --git a/src/fenrirscreenreader/screenDriver/vcsaDriver.py b/src/fenrirscreenreader/screenDriver/vcsaDriver.py
index aef34b4e..a71af4a6 100644
--- a/src/fenrirscreenreader/screenDriver/vcsaDriver.py
+++ b/src/fenrirscreenreader/screenDriver/vcsaDriver.py
@@ -126,8 +126,10 @@ class driver(screenDriver):
                 "default",  # fontfamily
             ]
         )  # end attribute )
+        # Use threading instead of multiprocessing to avoid pickle issues
+        # with self.env (which contains unpicklable file handles)
         self.env["runtime"]["ProcessManager"].add_custom_event_thread(
-            self.update_watchdog, multiprocess=True
+            self.update_watchdog, multiprocess=False
         )
 
     def get_curr_screen(self):