[Freeswitch-users] IVR UI/UX design

Hi all, My organization runs a number of IVR systems for information delivery, and one issue we often run into is that users find the interface a bit awkward or hard to navigate. We have experimented quite a bit internally with adjusting the structures of menus, ordering, phrasing etc. But we feel like there must be some knowledge/experience out there and that it shouldn't be necessary to rediscover most of this ourselves. Does anyone have recommendations for resources with info on best practices for IVR design? Or contacts in organizations/companies that have a lot of experience with this? Kind regards, Sam