A cocktail waitress and friend of Michael Jackson's doctor Conrad Murray recounted how she heard mumbling and coughing while on the phone to him at around the time the singer was dying. Sade Anding testified that Murray called her at 11:51 am on June 25, 2009, when she was in Houston and he was at Jackson's rented mansion, trying to help the star get to sleep. About five or six minutes into the conversation she realized that Murray was no longer answering, and the sound became muffled, as if the telephone was in a pocket. "I said 'Hello, Hello,' and I didn't hear anything .. I pressed the phone to my ear," she told the LA Superior Court. "I heard mumbling of voices . ...and I heard coughing," she added. She listened to the muffled noises for about three to four minutes before hanging up, she said, adding that she tried twice to call him back, but got no answer. Murray is accused of involuntary manslaughter over the singer's death, allegedly by administering an overdose of the powerful sedative propofol while trying to help Jackson with his insomnia. The trial has already heard from paramedics who arrived at Jackson's Holmby Hills mansion at 12:26 pm after receiving a 911 call at 12:21 pm -- about 20 minutes after the mysteriously-ended phone call with Anding. Anding had met Murray in February 2009 at a steakhouse restaurant in Houston, where the doctor came in as a guest. The pair stayed in touch over the next four months, up to Jackson's death, the court heard. She said the pair were friends, although Murray once "playfully" referred to her as his girlfriend. The waitress recalled how the following month she was told that LA detectives were trying to contact her. She called Murray to tell him about the interest from the LA Police Department (LAPD). "He told me, 'Why are they calling you? I'm so sorry they're contacting you'," she said, before giving her his lawyer's details, and telling her to call the attorney before getting back to the LAPD. The court also heard Tuesday from Nicole Alvarez, who was living with Murray and had a son by him in March 2009, and still lives with him in her apartment in Santa Monica. Alvarez, a 29-year-old actress who met Murray in a club in Las Vegas in 2005, described how Murray would routinely leave at around 9:00 pm to look after Jackson, and return the next morning. The trial has heard testimony about how the 58-year-old medic would stay at Jackson's mansion overnight to care for the singer, who was also regularly seeing a dermatologist and was found to be on a cocktail of drugs when he died. Alvarez also told of her excitement when the doctor surprised her by introducing her to Jackson. "I was speechless when I met him. I couldn't believe I was meeting Michael Jackson," she said, an excited smile on her face. Jackson was "interested" in her baby son, who was born three months before the star's death. "He wanted to schedule visits so that he could see my son," she told the court. In the final months of his life they were busy preparing to leave for London, to accompany Jackson on his "This Is It" series of concerts at the O2 Arena, for which he was rehearsing when he died. "I thought I was going to see the show," she said, adding: "I never finished packing."