She may of had a foreign couple staying with her and she tried to pass it off as a phone glitch. This happened to me in the past. My girlfriend unbeknownst to me was in a thruple with an Austrian couple. We were living in differed cities at the time. I’d call her to talk and I here people speaking German in the background—sometimes techno music. She tell me it was just a crossed lined. Eventually I did a surprise visit. The couple was home and she was out shopping. I stayed and waited for her. The look on her face when she saw me on waiting for her in their apartment was priceless. After that I sold all my possessions and joined the Peace Corp.