# Voice Call Audio Quality Degradation between a Subset of Twilio United States Phone Numbers and T-Mobile in United States - Provider: [Twilio](https://down.guide/twilio) - Level: confirmed - Impact: Degraded - lasted 2d 5h - started 2026-05-11 16:04 UTC - Voice, North America - us - id: DWN-77101dd52e - Official page: https://stspg.io/gfdw19qd5pcq ## Updates from Twilio ### 2026-05-11 16:04 UTC: investigating Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team is actively investigating this issue. We will provide another update in 1 hour or as soon as more information becomes available. ### 2026-05-11 16:27 UTC: identified Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 1 hour or as soon as more information becomes available. ### 2026-05-11 17:30 UTC: identified Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 2 hours or as soon as more information becomes available. ### 2026-05-11 19:31 UTC: identified Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 4 hours or as soon as more information becomes available. ### 2026-05-11 23:31 UTC: identified Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 8 hours or as soon as more information becomes available. ### 2026-05-11 23:43 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 2 hours or as soon as more information becomes available. ### 2026-05-12 01:49 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 4 hours or as soon as more information becomes available. ### 2026-05-12 05:55 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 8 hours or as soon as more information becomes available. ### 2026-05-12 13:55 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 16 hours or as soon as more information becomes available. ### 2026-05-12 15:58 UTC: identified Twilio customers may be experiencing voice call audio quality degradation between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States. Our team has identified the cause, and is working to resolve the issue. We will provide another update in 1 hour or as soon as more information becomes available. ### 2026-05-12 16:58 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 2 hours or as soon as more information becomes available. ### 2026-05-12 18:59 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 4 hours or as soon as more information becomes available. ### 2026-05-12 23:00 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 8 hours or as soon as more information becomes available. ### 2026-05-13 07:00 UTC: monitoring We have observed a recovery in voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States and are monitoring service stability. We will provide another update in 16 hours or as soon as more information becomes available. ### 2026-05-13 21:11 UTC: resolved The incident has been resolved and voice calls between a subset of Twilio United States Phone Numbers and T-Mobile network subscribers in the United States are operating normally. --- down.guide reads providers' official status pages every minute and adds its own evidence, always labeled. Free, no account. Agents: MCP at https://down.guide/mcp, REST at https://down.guide/api/v1, feeds at https://down.guide/feed. Built by Sazabi (https://sazabi.com/?utm_source=down-guide&utm_medium=markdown).