As segwit is active on testnet, blocks will only be downloaded from NODE_WITNESS peers. Though, exactly those peers are disconnected after `BLOCK_STALLING_TIMEOUT = 2` seconds. I am running master (6e6ab2c)

This behavior is consistent across restarts. Sample [debug.log](http://pastebin.ubuntu.com/23058327/) and [getchaintips](http://pastebin.ubuntu.com/23058325/).

It is possible that I shot my own foot at some point, but it seemed smelly enough to create an issue.

strGUI = _("This is a pre-release test build - use at your own risk - do not use for mining or merchant applications");
    }
    if (GetBoolArg("-testsafemode", DEFAULT_TESTSAFEMODE))
        strStatusBar = strRPC = strGUI = "testsafemode enabled";
    
    if (strMiscWarning != "")
    {
        strStatusBar = strMiscWarning;
        strGUI += (strGUI.empty() ? "" : uiAlertSeperator) + strMiscWarning;
    }
    if (fLargeWorkForkFound)
    {
        strStatusBar = strRPC = "Warning: The network does not appear to fully agree! Some miners appear to be experiencing issues.";
        strGUI += strGUI.empty() ? "" : uiAlertSeperator + _("Warning: The network does not appear to fully agree! Some miners appear to be experiencing issues.");
    }
    else if (fLargeWorkInvalidChainFound)
    {
        strStatusBar = strRPC = "Warning: We do not appear to fully agree with our peers! You may need to upgrade, or other nodes may need to upgrade.";
        strGUI += strGUI.empty() ? "" : uiAlertSeperator + _("Warning: We do not appear to fully agree with our peers! You may need to upgrade, or other nodes may need to upgrade.");
    }
    if (strFor == "gui")
        return strGUI;
    else if (strFor == "statusbar")
        return strStatusBar;
    else if (strFor == "rpc")
        return strRPC;
    assert(!"GetWarnings(): invalid parameter");
    return "error";
}
bool static AlreadyHave(const CInv& inv) EXCLUSIVE_LOCKS_REQUIRED(cs_main)