What is the problem with loading a json file from the server (.get jquery)?

Question

JavaScript

Hello!
I'm trying to run a currency chart .
Here it is
. It works like this: For each timeframe and each currency, there is a json file with a history (A chart is built based on these files)
These files are changed 5 times per second by a php script (The script is called by a program on the server, stupidly request

pol.vefx.ru/data.php

And also 5 times per second the chart is updated on the client (Javascript) - a new history is loaded and the chart is updated based on it ($.get() loading)
The problem is that periodically some of the charts stop, this is due to the fact that the file json with the history for this chart, the client constantly loads the same one (Although it changes on the server, the php script works)
After a while, everything comes back to normal
Server on windows

Answer 1

get json it is necessary to use the
second data in php is displayed differently each time, the reason is unknown