Updating FW will not get you higher transfers speed. You need to let us know what you think is wrong so we can help you find a solution.
What ISP service do you have?
What ISP modem do you have? Make and model
What FW is currently loaded on the router?
How are you connecting to the router? Wired or wireless?
What Wireless modes are currently set?
What Operating systems are you using on your devices?
What devices are you connecting to the router?
Things like this will help us to help you...