webdriver hangs when get or click

Same times the webdriver hangs when get url or click some link,  webdriver executing (get or click) but no done.

1. For firefox

FirefoxProfile fp = new FirefoxProfile();
fp.setPreference("webdriver.load.strategy", "unstable");
driver = new FirefoxDriver(fp);

2. For IE

profile is not support for IE, we can set attribute enablePersistentHover as false.

            DesiredCapabilities iecaps = DesiredCapabilities.internetExplorer();

            iecaps.setCapability(InternetExplorerDriver.ENABLE_PERSISTENT_HOVERING, false);