Every time when I call to JanetT, in the beginning there is some noise. But in the lesson, the sound quality is getting better, and noise is fewer. I think Skype may calibrate the noise, but I'm not sure.
In the article, I know 5G network is launched in South Korea and US. In Japan, 5G will be released in this year. I'm looking forward to see it, though Apple will launch 5G compatible iPhone in 2020 or later. I'm not sure I can wait until releasing that iPhone.