I'm driving now, so I'm sorry if it's hard to hear.
I'm driving, so there is a lot of traffic noise.
These are good short ways to say it.
If you want to say everything that you said in Japanese at one time, you could say,
"I'm driving now, so it may be hard to hear with all of the traffic noise."
これらは簡潔で良い言い方です。
補足説明にお書きになったことを一度に全て言いたいなら、次のように表せます。
"I'm driving now, so it may be hard to hear with all of the traffic noise."
「今運転中なので、車の騒音で聞こえにくいかもしれません」
アメリカ合衆国 
フィリピン 
