Optimum is the first landline telephone service provider in the U.S. to launch High Definition calling. HD calling is the next generation of voice technology that gives you less background noise, sharper sound quality and increased clarity in your phone conversations. To experience HD calling, customers and call recipients must subscribe to Optimum Voice and use HD-capable handsets.
Advanced greetings provide additional functionality for power users, but require additional setup. Contact the UBIT Help Center if you are interested in any of these options and require assistance:

Sound Telecom, through its Solaxis division, combines business voicemail, fax and auto-attendant services all in one optimized system. Our cloud based voicemail systems are mobile and PC accessible. Setup takes only minutes and services can be provided anytime, anywhere nationwide. Our web-enabled systems do not require physical office space or traditional hard-wired phone service. Welcome to the new age of cloud-based communications. We use the power of the Internet to allow you to easily communicate with whomever you choose in the most professional, responsive and cost-effective way possible.
Translation: If you sound unsure, then your current clients, prospects, and partners won’t be so sure about you either.