Does SONY VAIO VPC SA25GG/BI connect poorly?

Hello,

I am using SONY VAIO VPC SA25GG/BI but I notice my computer connects wifi very weakly.

At the same distance, I've compared it to a MacBook Air and an iPhone 7. However, the SONY VAIO VPC SA25GG / BI can not connect to the wifi network while MacBook Air and iPhone 7 still join the wifi network normally.

Is there anybody having a bug with wifi like me?

I have contacted Sony's warranty department and my computer is being inspected by the staff. I will update when there is new information on the cause of this problem.

Thanks,