Internet speed slows dramatically after just a few minutes of use [Ubuntu 14.04]

I've recently dual booted Ubuntu 14.04 with Windows 10. Initially on Ubuntu, it will run perfect with a download of ~40MB/S. After around 5 minutes, it slows down to ~2MB/S with a sporadic on/off coection which can dip as low as 10KB/S. This continues until I reboot the laptop, where it will run for another few minutes and then slow.

This issue is prevalent regardless of browser used or WiFi network coected to.
There are no issues on the Windows 10 partition, which maintains a steady ~40MB/S.

If helpful, ruing the command:

sudo lshw -C network

*-network
description: Wireless interface
product: BCM4352 802.11ac Wireless Network Adapter
vendor: Broadcom Corporation
physical id: 0
bus info: pci@0000:02:00.0
logical name: wlan0
version: 03
serial: ac:d1:b8:c0:94:81
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list etheet physical wireless
configuration: broadcast=yes driver=wl0 driverversion=6.30.223.248 (r487574) ip=192.168.1.15 latency=0 multicast=yes wireless=IEEE 802.11abg
resources: irq:19 memory:f7200000-f7207fff memory:f7000000-f71fffff