Browning on MQ3 Sides

I've had my MQ3 for about a year now and I've notices the side straps (the ones with the charging port and the 3m Jack, not the ones around your head) Have been getting a brownish color, Especially on the edges, Anyway to clean this off as it is very unpleasing.

I've had my MQ3 for about a year now and I've notices the side straps (the ones with the charging port and the 3m Jack, not the ones around your head) Have been getting a brownish color, Especially on the edges, Anyway to clean this off as it is very unpleasing.