Returning the Tinny EVT Unit Is Part of Root-Cause Control

The acceptance condition for Returning the Tinny EVT Unit Is Part of Root-Cause Control only became clear after the system was split into boundaries. When the LOUP speaker was reported as very tinny, the manufacturer requested the unit back together with a tested speaker reference.

That creates a controlled comparison on the same bench and avoids arguing from different samples, rooms or firmware assumptions. The returned unit can be electrically driven, opened, inspected and compared against a known part while preserving the original failure.

The design became clearer when configuration, runtime state and recovery behaviour were specified separately instead of being implied by implementation details. Evidence marker: return-tinny-unit.

Physical failures need physical evidence. Do not destroy or retune the only failing sample before the cause is understood. Once that contract is written down, firmware and server changes can be reviewed against the same expectation instead of relying on memory.

Project evidence

LOUP engineering marker: return-tinny-unit. This note records the design or debugging lesson without publishing device credentials, private keys, customer data or manufacturing secrets.