Background noises can be picked up in voicemail recordings, and even though we may not want them to, they do subversively impact how our messages are received. Noisy backgrounds tend to trigger thoughts of a chaotic atmosphere --implying that you are disorganized or do not consider the content of your message to be important enough to be heard clearly. And if you don’t care about what you’re trying to say, why should the person on the other end of the phone?
5 Steps to Leaving Voicemail Messages That Get Returned: Identify Yourself. Say who you are and the company you work for up front. This makes you sound professional and transparent. S ay Your Phone Number Twice. Prospects can’t call back if they don’t have or you garbled your number. Give your contact information upfront and say it twice

Instead, close out by saying something to the effect of, “I look forward to speaking with you soon”, or even “Call me at your earliest convenience.” Even though all these examples communicate the same thing, they take different approaches to the call back request, and little things like wording make all the difference.
At the same time, if the prospect can’t hear or understand you, all of your work is wasted. Drink water, clear your throat, and invest in a good headset or phone. Be aware of your accent or the way you say words or numbers. And, avoid sales speak and buzzwords.