In fast-paced sales, every second counts. A parallel dialer helps sales teams connect with more prospects by dialing multiple numbers simultaneously, but dialer latency can slow down productivity and hurt the caller experience. If your sales reps experience delays when connecting with prospects, it could lead to lost opportunities and frustrated leads.

In this post, we’ll explore the main causes of dialer latency and how to reduce or eliminate delays for smoother sales conversations.

What Is Dialer Latency?

Dialer latency refers to the delay between when a sales rep initiates a call and when the prospect actually hears their voice. In extreme cases, this delay can last several seconds, causing confusion and making it obvious that the call is automated—reducing the chances of a positive engagement.

Latency can occur in different stages of the dialing process, including:

• The time it takes to connect a call
• The delay before the prospect hears the caller’s voice
• Gaps in audio transmission between the caller and recipient

Causes of Dialer Latency

1. VoIP Connection Issues

‍Most modern parallel dialers use Voice over Internet Protocol (VoIP) to make calls. If your internet connection is unstable or too slow, it can cause delays in voice transmission, resulting in noticeable latency.How to fix it:

• Ensure your internet speed meets VoIP requirements (at least 5 Mbps upload/download per user).
• Use a wired Ethernet connection instead of Wi-Fi.
• Prioritize VoIP traffic with Quality of Service (QoS) settings on your router.

2. Dialer Call Routing & Connection Time

Dialers often route calls through multiple carriers or servers before reaching a prospect. If your dialer uses inefficient routing or low-quality providers, this can introduce additional seconds of delay.How to fix it:

• Choose a dialer with intelligent call routing that connects via the fastest and most reliable carriers.
• Monitor your provider’s Answer-Seizure Ratio (ASR) and Post Dial Delay (PDD) to ensure fast call connections.

3. Over-Aggressive Call Pacing

‍Some parallel dialers attempt to connect too many calls at once, leading to backend processing delays. If your system is dialing at an extremely high speed, it may take longer to bridge calls when a recipient answers.How to fix it:

• Optimize your calls per agent setting to balance speed and call quality.
• Adjust pacing based on real-time call connection rates.

4. Call Bridging & Answer Detection Issues

‍Parallel dialers use answering machine detection (AMD) to filter out voicemail responses. However, if this feature is slow or inaccurate, it can create unnecessary pauses before connecting a rep to a live person.How to fix it:

• Use a dialer with AI-powered voicemail detection for faster and more precise call routing.
• Test your AMD settings to find the optimal balance between accuracy and speed.

5. Latency from Cloud-Based Dialers

‍Cloud-based dialers introduce an additional layer of processing compared to on-premise PBX systems. If your dialer’s cloud infrastructure isn’t optimized, it can lead to unnecessary lag.How to fix it:

• Choose a dialer provider with low-latency cloud infrastructure.
• Verify that your provider has data centers near your target call locations.

6. Agent or Software Delays

‍Even if the dialer itself is working well, delays can occur when a rep doesn’t start speaking immediately after a call connects. Additionally, if your CRM integration is slow, it may take extra time to load prospect information.‍

How to fix it:

• Train reps to start talking as soon as the call connects.
• Use a dialer with Live Transcription and prospect previews to allow agents to feel prepared .

Debugging Dialer Latency: A Step-by-Step Breakdown

Whether you're building or maintaining a dialer, identifying the root cause of delay requires a structured approach—analyzing each component in the call path from client to server to recipient.

1. Client-Side Latency: Network and Hardware

The first step in diagnosing dialer latency is checking for delays on the caller’s side. Since most dialers operate over VoIP (Voice over Internet Protocol), network stability is a major factor.

Key Debugging Steps:

• Check network speed & jitter: Use tools like ping, traceroute, or Wireshark to measure packet loss and round-trip time. High jitter (>30ms) or packet loss can introduce audible delays.
• Switch to a wired connection: Wi-Fi adds unpredictable latency due to interference. A direct Ethernet connection reduces variability.
• Inspect local CPU & memory usage: If the dialer software runs locally, system resource exhaustion can slow down call initiation. Monitor CPU/memory usage during calls.
• Run a speed test of your network: https://networktest.twilio.com
• Check browser or softphone processing: If using a browser-based dialer, ensure WebRTC functions properly by testing with chrome://webrtc-internals/ or similar tools.

Potential Fixes:

• Prioritize VoIP traffic with Quality of Service (QoS) settings on the router.
• Reduce other high-bandwidth processes running on the client machine.
• If using a softphone, switch to a dedicated VoIP device to compare performance.

2. Server-Side Latency: Call Routing & Processing DelaysOnce the client initiates a call, the request is sent to the dialer’s backend server or cloud PBX system. Delays here can arise from inefficient call routing, slow database queries, or high server load.Key Debugging Steps:

• Measure API response times: Check how long it takes for the dialer’s backend to process call initiation (POST /call or similar API). If responses exceed 100-200ms, investigate server-side inefficiencies.
• Analyze call bridging time: Look at logs to measure how long the server takes to connect a rep after a recipient picks up. High Post Dial Delay (PDD) can indicate slow carrier handoff.
• Inspect answering machine detection (AMD) logic: If AMD is enabled, excessive processing time can create noticeable pauses. Check logs for AMD processing duration.
• Load test server capacity: Use stress testing tools (k6, JMeter) to simulate concurrent calls and identify performance bottlenecks.

Potential Fixes:

• Optimize database indexing and queries to speed up call initiation.
• Implement low-latency call routing algorithms that prioritize the fastest carrier path.
• Use real-time monitoring tools (Datadog, Prometheus) to track call processing delays.
• Reduce AMD complexity or disable it for high-speed outbound campaigns.

3. Carrier & PSTN Latency: External Routing DelaysOnce the dialer server initiates the call, it is handed off to a VoIP carrier or Public Switched Telephone Network (PSTN). Latency in this stage often results from:

• Poor carrier selection (low-quality VoIP routes)
• Inefficient Least Cost Routing (LCR)
• Long-distance call termination delays

Key Debugging Steps:

• Test multiple carriers: Route calls through different providers (e.g., Twilio, Bandwidth, Telnyx) and measure call setup times.
• Compare VoIP vs. PSTN handoff time: If VoIP calls are faster than PSTN, the issue may be related to circuit-switched network delays.
• Check carrier latency metrics: Look at Answer-Seizure Ratio (ASR) and Average Call Setup Time (ACST) in carrier logs.
• Monitor SIP signaling delays: Use sngrep or Wireshark to inspect SIP INVITE responses and identify slow steps in call negotiation.

Potential Fixes:

• Work with a Tier 1 VoIP provider for better call routing.
• Adjust Least Cost Routing (LCR) thresholds to favor lower-latency carriers over cost savings.
• Use geographically closer data centers to reduce network traversal time.

4. Recipient-Side Latency: Audio Transmission & Response TimeEven if the call reaches the recipient, additional delays can occur due to audio transmission issues or the recipient’s network conditions.Key Debugging Steps:

• Check for one-way audio or high jitter: If the recipient hears a delay before the agent speaks, test round-trip latency using VoIP testing tools (pingtest.net, VoIPmonitor).
• Measure codec negotiation time: Some VoIP carriers perform codec transcoding (e.g., converting G.711 to Opus), which can add milliseconds of delay.
• Inspect handset or softphone response time: Some mobile networks introduce additional latency compared to landlines or VoIP endpoints.

Potential Fixes:

• Use low-latency audio codecs (Opus, G.711) to avoid unnecessary transcoding.
• If targeting mobile numbers, prefer VoIP-to-mobile direct routes over PSTN

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Final Thoughts

Latency in a parallel dialer can be a frustrating issue, but most delays can be minimized with the right setup. By optimizing your network, using high-quality call routing, adjusting call pacing, and selecting a low-latency dialer, you can ensure a smoother experience for both your sales team and prospects.If you're looking for a high-performance, low-latency parallel dialer with minimal delays, check out Bearworks—our AI-powered sales dialer designed for speed, efficiency, and high-quality connections. Need help improving your team's call performance? Contact us today to learn more!

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