Crash when closing a serial port session

Howdy. I started getting app crashes when I exit serial port sessions. This started after I added some additional USB to serial adapters. I am attempting to connect 13 console ports to my management box for OOBM. RDM didn't crash when I had about six USB to serial adapters and I haven't had time to go through and unplug some to see if there is a tipping point. Here are the error messages from the Windows event log. If anyone has any thoughts, I would appreciate it.

Log Name: Application
Source: .NET Runtime
Date: 2/1/2026 11:42:04 PM
Event ID: 1026
Task Category: None
Level: Error
Keywords: Classic
User: N/A
Computer: xxxxx
Description:
Application: RemoteDesktopManager.exe
CoreCLR Version: 9.0.1125.51716
.NET Version: 9.0.11
Description: The process was terminated due to an unhandled exception.
Exception Info: System.NullReferenceException: Object reference not set to an instance of an object.
at Devolutions.Protocols.Core.SerialClient.WindowsPort.<>c__DisplayClass41_0.<ReadBufferAsync>b__0(UInt32 errorCode, UInt32 numBytes, NativeOverlapped* overlappedPtr)
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
--- End of stack trace from previous location ---
at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state)
at System.Threading.PortableThreadPool.IOCompletionPoller.Callback.Invoke(Event e)
at System.Threading.ThreadPoolTypedWorkItemQueue`2.System.Threading.IThreadPoolWorkItem.Execute()
at System.Threading.ThreadPoolWorkQueue.Dispatch()
at System.Threading.PortableThreadPool.WorkerThread.WorkerThreadStart()

Faulting application name: RemoteDesktopManager.exe, version: 2025.3.29.0, time stamp: 0x68f20000
Faulting module name: KERNELBASE.dll, version: 10.0.14393.8688, time stamp: 0x6930ff99
Exception code: 0xe0434352
Fault offset: 0x0000000000026ea8
Faulting process id: 0x2c40
Faulting application start time: 0x01dc93d435613a8e
Faulting application path: C:\Program Files\Devolutions\Remote Desktop Manager\RemoteDesktopManager.exe
Faulting module path: C:\Windows\System32\KERNELBASE.dll
Report Id: c71e72fc-bf30-46c6-a5dc-9f1c1a2806ab
Faulting package full name:
Faulting package-relative application ID: