What does this sentence mean? "music to one's ears phrase of music", how to understand it? Thank you so much!

How to translate this sentence? "If I was to leave when you need me most",doesn‘t it mean " I won’t leave you when you need me "? How to understand and use this sentence pattern? Thanks a lot!

My Job Hello,everyone: Nice to meet you ,and I am glad to be here. I am Sally,come from Chang Chun.A city in the northeast of China.I have married this year.I like to see some English TV palys,such as Downton Abbey.I like the culture.It is noble,but a little indifference. Well,I have been working for 2 years as a SAP data manager in a auto parts company.My main work is to enter the production data into the system,including the production BOM,the production route and the production version to make other parts in the company can use the material master data. And I must to make sure that what I have entered is right,otherwise it will be trouble for everyone. People say that it is boring,but I like it.Beacuse it is organized.I can get the information from my colleagues,then I just to do it by myself.But I must be very careful. So will you like the job?

The meaning of the sentence "I suppress a smile",How to translate it in Chinese?Does it smile or not?

Wed.Jul.20,2016 Today is cloudy,but the air is hot and stuffy.When I arrived at the company,it is stuffier than outside.I am drinking a bottle of flower tea,doing my work.I feel more sober than before.Otherwise,I know some new words:"tummy,whisle,crowd,harsh".Hope that I can remember them tomorrow .