diff --git a/backend/app/services/bambu_ftp.py b/backend/app/services/bambu_ftp.py
index 8085db1c3..dafc59234 100644
--- a/backend/app/services/bambu_ftp.py
+++ b/backend/app/services/bambu_ftp.py
@@ -78,7 +78,8 @@ class BambuFTPClient:
     FTP_PORT = 990
     DEFAULT_TIMEOUT = 30  # Default timeout in seconds (increased for A1 printers)
     # Models that need SSL session reuse disabled (A1 series has FTP issues with session reuse)
-    SKIP_SESSION_REUSE_MODELS = ("A1", "A1 Mini", "P1S", "P1P", "P2S")
+    # P2S should use normal session reuse like X1C/P1S, not skip it
+    SKIP_SESSION_REUSE_MODELS = ("A1", "A1 Mini", "P1S", "P1P")
 
     def __init__(
         self,
diff --git a/backend/app/services/bambu_mqtt.py b/backend/app/services/bambu_mqtt.py
index ec27a3dc4..4346510fe 100644
--- a/backend/app/services/bambu_mqtt.py
+++ b/backend/app/services/bambu_mqtt.py
@@ -249,6 +249,7 @@ class BambuMQTTClient:
         ip_address: str,
         serial_number: str,
         access_code: str,
+        model: str | None = None,
         on_state_change: Callable[[PrinterState], None] | None = None,
         on_print_start: Callable[[dict], None] | None = None,
         on_print_complete: Callable[[dict], None] | None = None,
@@ -258,6 +259,7 @@ class BambuMQTTClient:
         self.ip_address = ip_address
         self.serial_number = serial_number
         self.access_code = access_code
+        self.model = model
         self.on_state_change = on_state_change
         self.on_print_start = on_print_start
         self.on_print_complete = on_print_complete
@@ -2075,6 +2077,12 @@ class BambuMQTTClient:
                 }
             }
 
+            # P2S-specific parameter adjustments
+            # P2S printer doesn't support vibration calibration like X1/P1 series
+            if self.model and self.model.upper().strip() in ("P2S", "N7"):
+                command["print"]["vibration_cali"] = False
+                logger.info(f"[{self.serial_number}] P2S detected: disabling vibration_cali")
+
             # Add AMS mapping if provided
             if ams_mapping is not None:
                 command["print"]["ams_mapping"] = ams_mapping
@@ -2083,7 +2091,16 @@ class BambuMQTTClient:
             logger.info(f"[{self.serial_number}] Sending print command: {json.dumps(command)}")
             self._client.publish(self.topic_publish, json.dumps(command), qos=1)
             return True
-        return False
+        else:
+            # Log why we couldn't send the command
+            if not self._client:
+                logger.error(f"[{self.serial_number}] Cannot start print: MQTT client not initialized")
+            elif not self.state.connected:
+                logger.error(
+                    f"[{self.serial_number}] Cannot start print: Printer not connected (client exists but disconnected). "
+                    f"Connection state: {self.state.connected}, Last message: {self._last_message_time}"
+                )
+            return False
 
     def stop_print(self) -> bool:
         """Stop the current print job."""
diff --git a/backend/app/services/print_scheduler.py b/backend/app/services/print_scheduler.py
index 0e8a04d47..e60e7efa7 100644
--- a/backend/app/services/print_scheduler.py
+++ b/backend/app/services/print_scheduler.py
@@ -1004,17 +1004,22 @@ class PrintScheduler:
                 pass  # Don't fail if MQTT fails
         else:
             item.status = "failed"
-            item.error_message = "Failed to send print command"
+            item.error_message = "Failed to send print command to printer"
             item.completed_at = datetime.utcnow()
             await db.commit()
-            logger.error(f"Queue item {item.id}: Failed to start print")
+            logger.error(
+                f"Queue item {item.id}: Failed to start print on {printer.name} ({printer.model}) - "
+                f"printer_manager.start_print() returned False. "
+                f"This may indicate: printer not connected, MQTT error, unsupported model configuration, or firmware issue. "
+                f"Check printer status and backend logs for details."
+            )
 
             # Send failure notification
             await notification_service.on_queue_job_failed(
                 job_name=filename.replace(".gcode.3mf", "").replace(".3mf", ""),
                 printer_id=printer.id,
                 printer_name=printer.name,
-                reason="Failed to send print command",
+                reason="Failed to send print command to printer - check printer connection and status",
                 db=db,
             )
 
diff --git a/backend/app/services/printer_manager.py b/backend/app/services/printer_manager.py
index c02ea743b..c0e6e8a81 100644
--- a/backend/app/services/printer_manager.py
+++ b/backend/app/services/printer_manager.py
@@ -192,6 +192,7 @@ class PrinterManager:
             ip_address=printer.ip_address,
             serial_number=printer.serial_number,
             access_code=printer.access_code,
+            model=printer.model,
             on_state_change=on_state_change,
             on_print_start=on_print_start,
             on_print_complete=on_print_complete,