Hello Wurpe Hosting,
Yes, it happen intermittent. Sometimes it will be okay after few minutes, but sometimes will be few hour even whole day.
For the pulgins, as I have 4 websites, different website install different plugins.
And I had verified this is not the host related issue, as when I am not able to access the websites, they can. They provide a proxy site and I am able to access the website by using a proxysite when it is not working.
Thanks.