Connect Your PBX to AI: Two-Way Integration That Transforms Customer Experience

The most common misconception about AI voice agents? That you need to replace your entire phone system to use them.

The reality is different. If you're running 3CX, Asterisk, FreePBX, or any SIP-compatible PBX, you can connect it to Mihu AI today—without touching your existing infrastructure. Your current dial plans, ring groups, and extensions all stay exactly where they are. AI simply becomes another extension on your system, ready to handle calls or receive transfers.

This guide shows you exactly how to set this up—both from a business perspective (what becomes possible) and a technical perspective (how to configure it). By the end, you'll understand how to create a seamless customer experience where AI and humans work together through your existing phone system.

Why Connect Your PBX to AI?

Before diving into the technical setup, let's address the fundamental question: what does PBX integration actually give you?

In modern customer service, the biggest pain points aren't usually about the technology itself—they're about availability, consistency, and speed. Customers call outside business hours and get voicemail. They wait on hold during busy periods. They navigate confusing IVR menus pressing buttons for options that don't quite match what they need. They repeat their issue to multiple agents after transfers.

PBX-integrated AI solves these problems without requiring you to change how your team works. Your receptionists, sales reps, and support agents keep using the same phones and extensions they always have. The AI handles everything else—the overflow, the after-hours calls, the routine inquiries that don't need human attention.

Two Integration Methods: Choose What Works for Your Business

Mihu AI offers two complementary ways to integrate with your PBX. You can use one or both depending on your needs:

The power comes from using both together. AI becomes your first line of defense for incoming calls, handling what it can and routing what it can't. Simultaneously, your PBX can forward overflow calls, after-hours calls, or specific request types directly to AI.

Method 1: AI Transfers Calls to Your Team via SIP URI

This is Mihu AI's most powerful routing capability. When a caller needs to speak with a human—or when their request matches specific criteria you've defined—the AI transfers them directly to any extension on your PBX using standard SIP URI format.

No IVR menus. No "press 1 for sales." The caller simply says what they need, and the AI routes them intelligently.

SIP URI Format for Transfers

Configure your transfer destinations using standard SIP URIs that point directly to extensions on your PBX:

# Standard format
sip:{extension}@{your_pbx_address}

# Department Extensions
sip:100@pbx.yourcompany.com    # Sales ring group
sip:101@pbx.yourcompany.com    # Support queue
sip:102@pbx.yourcompany.com    # Billing department
sip:103@pbx.yourcompany.com    # Reception desk

# Individual Extensions
sip:201@pbx.yourcompany.com    # Account manager - John
sip:202@pbx.yourcompany.com    # Technical lead - Sarah
sip:210@pbx.yourcompany.com    # CEO direct line

# Special Routing
sip:300@pbx.yourcompany.com    # VIP customer queue
sip:911@pbx.yourcompany.com    # Emergency escalation

Intelligent Routing Examples

The AI doesn't just match keywords—it understands intent. Here's how routing rules work in practice:

Method 2: Your PBX Routes Calls to AI

The second integration method works in the opposite direction. Register Mihu AI as an extension on your PBX, then configure your dial plan to forward specific scenarios to that extension.

This is incredibly powerful for handling situations your current setup can't address—overflow, after-hours, specific request types that would otherwise go to voicemail.

How It Works

Scenarios Where PBX → AI Routing Excels

Sample Dial Plan Configuration

# No Answer Overflow
IF ring_group_100 no_answer_after = 15 seconds
THEN forward_to = extension_200 # Mihu AI

# After Hours Routing
IF time NOT BETWEEN 09:00 AND 18:00
THEN forward_to = extension_200 # Mihu AI

# Specific IVR Options
IF caller_presses = 4 # "Check order status"
THEN forward_to = extension_200 # Mihu AI

IF caller_presses = 5 # "Book appointment"
THEN forward_to = extension_200 # Mihu AI

# All Agents Busy
IF queue_100 wait_time > 60 seconds
THEN offer_callback via extension_200 # Mihu AI

Real-World Use Cases by Industry

Different businesses use PBX + AI integration in different ways. Here are scenarios we see most frequently:

Healthcare Clinics

Challenge: Front desk overwhelmed with appointment calls, patients waiting on hold, after-hours emergencies going to voicemail.

Solution:

• AI handles all appointment scheduling, rescheduling, and cancellations via SIP transfer to practice management system
• After-hours calls route to AI, which triages: urgent symptoms transfer to on-call doctor (sip:oncall@pbx), routine questions get scheduled callbacks
• Prescription refill requests handled entirely by AI, transferring to pharmacy queue only when needed

Result: 70% of calls handled without human intervention. Front desk focuses on in-person patients.

Auto Dealerships

Challenge: Sales calls going unanswered during test drives, service department overwhelmed with status checks, lost leads.

Solution:

• All inbound calls hit AI first—qualifies leads, captures contact info, books test drive appointments
• Hot leads ("I'm ready to buy today") transfer immediately to sip:sales@pbx with context
• "Is my car ready?" calls handled entirely by AI checking service management system
• After-hours inquiry? AI schedules callback for next business day with specific salesperson

Result: Zero missed leads. Service advisors handle 3x more customers. Sales conversion up 40%.

E-Commerce / Retail

Challenge: Order status calls overwhelming support team, repetitive questions eating agent time.

Solution:

• IVR option "track my order" routes directly to AI extension
• AI queries order management system, provides real-time status, estimated delivery
• Return/exchange requests handled by AI, only escalating to human when policy exception needed
• Product availability questions answered instantly from inventory database

Result: Support team handles 60% fewer calls. Average handle time down. CSAT scores up because agents aren't rushed.

Property Management

Challenge: Maintenance requests at all hours, tenant lockouts, showing requests overwhelming leasing office.

Solution:

• Emergency maintenance (flooding, no heat) transfers immediately to on-call tech: sip:emergency@pbx
• Routine maintenance logged by AI, work orders created automatically
• Showing requests handled entirely by AI—checks availability, schedules tour, sends confirmation
• Rent payment questions answered from tenant portal data

Result: 24/7 tenant support. Leasing staff focuses on closings. Emergency response time cut in half.

Technical Setup Guide

Now let's get into the technical details. Whether you're an IT administrator or working with one, this section covers everything needed to get Mihu AI connected to your PBX.

Firewall Configuration

Before Mihu AI can register to your PBX, your firewall must allow incoming connections from our servers. Add these IP addresses to your firewall whitelist:

Creating a SIP Extension on Your PBX

Create a new extension on your PBX specifically for Mihu AI. Configure it with these settings:

NAT-Safe Configuration

These settings on your PBX are critical for reliable operation. Without proper NAT configuration, you'll experience one-way audio, registration drops, and call failures.

PBX Configuration Examples

Asterisk / FreePBX (PJSIP)

Add the following to your pjsip.conf file to create the extension for Mihu AI:

; ==========================================
; Extension for Mihu AI Voice Agent
; ==========================================

; Authentication credentials
[mihu-ai-auth]
type = auth
auth_type = userpass
username = mihu_ai_ext
password = your_secure_password_here

; Address of Record (AOR)
[mihu-ai-aor]
type = aor
max_contacts = 1
remove_existing = yes
qualify_frequency = 30

; Endpoint configuration
[mihu-ai-endpoint]
type = endpoint
auth = mihu-ai-auth
aors = mihu-ai-aor
context = from-internal
disallow = all
allow = ulaw,alaw,g722
dtmf_mode = rfc4733

; NAT-safe settings (CRITICAL)
direct_media = no
rewrite_contact = yes
force_rport = yes
rtp_symmetric = yes

Entering Credentials in Mihu AI

Once your PBX extension is configured, enter the connection details in the Mihu AI dashboard:

Maximizing Efficiency: Integration Scenarios

The real power of PBX + AI integration comes from combining both methods strategically. Here are proven configurations that maximize efficiency:

Scenario 1: Full AI Front-Door with Smart Escalation

Configuration: All inbound calls route to Mihu AI first

# Inbound Call Flow
INCOMING → Mihu AI answers
    IF request = "order status" → AI handles completely
    IF request = "appointment" → AI books, no transfer
    IF request = "sales inquiry" → sip:100@pbx (hot lead)
    IF request = "complex issue" → sip:101@pbx (support)
    IF request = "speak to human" → sip:103@pbx (reception)

Efficiency gain: 60-70% of calls never reach human agents. Humans only handle calls that truly need their expertise.

Scenario 2: AI as Overflow Safety Net

Configuration: Human agents as primary, AI catches overflow

# Inbound Call Flow
INCOMING → Ring group 100 (Sales team)
    IF no_answer > 20 seconds → ext 200 (Mihu AI)
    IF all_agents_busy → ext 200 (Mihu AI)
    IF after_hours → ext 200 (Mihu AI)

# AI then handles or transfers back
AI → Handles request OR transfers to sip:xxx@pbx

Efficiency gain: Zero missed calls. 24/7 coverage without staffing costs. Peak periods handled seamlessly.

Scenario 3: Hybrid IVR Replacement

Configuration: Replace traditional IVR menu with AI-powered routing

# BEFORE: Traditional IVR
"Press 1 for Sales, 2 for Support, 3 for Billing..."
# Customer frustration: 45% abandon rate

# AFTER: AI-Powered Routing
"Hello, how can I help you today?"
Customer: "I have a question about my bill"
AI: Handles directly OR transfers to sip:102@pbx
# Abandon rate: 8%

Efficiency gain: 80% reduction in call abandonment. Average handle time reduced. Customer satisfaction scores increase significantly.

Measuring Integration Success

Troubleshooting Guide

Common issues and their solutions when connecting Mihu AI to your PBX:

Debug Commands for Your PBX

Use these commands on Asterisk/FreePBX to diagnose issues:

# Check if Mihu AI is registered
asterisk -rx "pjsip show endpoints"

# View registration contacts
asterisk -rx "pjsip show contacts"

# Enable SIP debug logging
asterisk -rx "pjsip set logger on"

# View active call channels
asterisk -rx "core show channels"

# Monitor logs in real-time
tail -f /var/log/asterisk/full

# Capture SIP traffic for analysis
tcpdump -i any -n port 5060 -w sip_debug.pcap

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