Aastra has announced the availability of a maintenance software release for the 67xi series and the 9143i, 9480i, 9480i CT SIP telephones
Release 2.5.2 delivers enhancements to previous functionalities and fixes, improving day-to-day use and deployment of Aastra IP phones. This release includes:

Speakerphone audio tuning enhancements
New configuration parameter to enable/disable the route header in the SIP [...]