Problem Statement
While the majority of inbound faxes are successfully received via T.38, isolated instances occur where certain senders transmit faxes using non-T.38 formats (typically voice/G.711). In these cases:

The system does not identify the call as a fax, treating it as a voice call.

The fax fails to be processed, and no fallback handling is in place.

The burden of resolution falls entirely on the sender, who may not have technical control over their fax equipment or carrier routing.

This results in negative customer impact, particularly when:

The sender is a critical third-party (e.g., government or financial institutions).

The sending carrier cannot or will not cooperate.

The customer expects consistent fax delivery regardless of the sending method.

Customer Impact
Lost or missed fax communications.

Operational disruption due to reliance on third-party sender configuration.

Increased support calls and escalations.

Frustration when faxes work inconsistently depending on the sending number.

Proposed Feature Enhancement
Inbound Fax Adaptation Mechanism:

Implement an optional override or exception rule at the account or number level to treat specific inbound calls as fax attempts based on known behavior (e.g., specific caller ID).

Allow system to detect known fax-like audio patterns over G.711 and route to fax processing modules.

Provide configurable fallback behavior if T.38 is not detected (e.g., auto-switch to audio-based fax detection or reroute to alternate fax system).

Benefits
Improved fax reliability and customer satisfaction.

Reduces dependency on third-party carrier behavior.

Enables more robust support for legacy fax environments.

Minimizes lost faxes due to protocol mismatches.

Limitations / Considerations
Risk of false positives: voice calls being misclassified as faxes.

Carrier-side limitations may still prevent end-to-end resolution.

Security and privacy implications of call classification need to be reviewed.

Next Steps
Review feasibility with Fax Service Engineering Team.

Evaluate scope of customer impact across reported cases.

Assess integration impact on current T.38 routing logic.

Develop logging or analytics feature to help detect fax attempts sent via non-T.38.