[BUG] Version 2.0.x very slow key input on Windows with Malwarebytes enabled

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

When running claude from a powershell 5 or 7, keyboard input is very slow and sporadic, initially not responsive. With each key entry, I notice the MBAMService process becomes very busy, taking 10-30% cpu.
I didn't experience this issue on 1.x.

What Should Happen?

Claude should respond normally, even with MB in use.

Error Messages/Logs

No error messages. Just very slow responses.

Steps to Reproduce

1. Run claude from Windows 11 powershell, either version 5 or 7
2. Type any command

Claude Model

Sonnet (default)

Is this a regression?

Yes, this worked in a previous version

Last Working Version

1.0.x

Claude Code Version

2.0.5

Platform

Anthropic API

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information