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btw, pls paste the error message of build matching php from command line if you like.
It is normal that you encounter problem due to varies resource limits applied by WHM, even cPanel itself instructs you to run easyapache from command line if problem with the web console interface.
Since you can do it from command line successfully, we believe it is the way how it works, no further investigation is required. If you have problem with command line as well, our staff will look into and fix it quickly.