MBP Retina: menu bar icons smoothness problem

Question

Hello everyone,
I recently switched to MBP Retina 2013, this is my first Mac and despite some software problems, I am loving it!
Here's my question/problem: sometimes (did not notice any logic when it happens) my menu bar icons lose their retina smoothness and look bad. Screenshot below shows how it looks. Notifications icon on the right is good, but spotlight and the others very bad, including date & time. Menu bar text items on the left (non icons) look fine.
Does anyone know what's causing this problem and how to fix it?
Thanks!

Answer 1

Hard to troubleshoot if it does it sometimes.
If the problem is still there, try booting into the Safe Mode using your normal account.  Disconnect all peripherals except those needed for the test. Shut down the computer and then power it back up. Immediately after hearing the startup chime, hold down the shift key and continue to hold it until the gray Apple icon and a progress bar appear. The boot up is significantly slower than normal. This will reset some caches, forces a directory check, and disables all startup and login items, among other things. When you reboot normally, the initial reboot may be slower than normal. If the system operates normally, there may be 3rd party applications which are causing a problem. Try deleting/disabling the third party applications after a restart by using the application un-installer. For each disable/delete, you will need to restart if you don't do them all at once.
Safe Mode
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