Ubuntu – WIreless connects but Internet stops working on Ubuntu 12.04 64 Bit and Broadcom 4313

I'm running Ubuntu 12.04 64 Bit on a HP Pavilion dm4. It has a Broadcom 4313 Wireless Adapter and a Realtek RTL8168D/8111D Ethernet Adapter.

I haven't been able to get consistent internet access from either the wireless or wired connection. On startup, or after restarting the router, I am able to load a couple of websites, but after that the internet stops working (though the wirless/ethernet continue to indicate that they are connected). Strangely, I am still able to do things with the websites I have already loaded – for example, loading/sending messages in gmail. It's just loading certain new websites that is the issue. Also, I still see available wireless networks.

This the relevant output from lspci -v:

02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03)
    Subsystem: Hewlett-Packard Company Device 1469
    Flags: bus master, fast devsel, latency 0, IRQ 42
    I/O ports at 2000 [size=256]
    Memory at c0404000 (64-bit, prefetchable) [size=4K]
    Memory at c0400000 (64-bit, prefetchable) [size=16K]
    Capabilities: <access denied>
    Kernel driver in use: r8168
    Kernel modules: r8168

03:00.0 Network controller: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller (rev 01)
    Subsystem: Hewlett-Packard Company Device 145c
    Flags: bus master, fast devsel, latency 0, IRQ 17
    Memory at c2400000 (64-bit, non-prefetchable) [size=16K]
    Capabilities: <access denied>
    Kernel driver in use: wl
    Kernel modules: wl, bcma, brcmsmac

I've tried blacklisting the different wireless drivers, but nothing seems to work, even if I try to force it to use the brcmsmac driver, which I've read elsewhere should be the correct one. For the ethernet, I also tried installing the latest driver (r8168 instead of r8169) and blacklisting the old one.

I'm dual booting windows 7 on the same laptop, but have no issues with either the wireless or ethernet connections.