on all hosts I have simple check which executes command

icmpping[,4,25,,{$PING_TIMEOUT}]

check is defined in template, and template is attached to other templates (and they are attached to hosts - so there are minimum 2-3 steps of inheritance). Macro PING_TIMEOUT = "2000".

When I use "traditional" proxies, it works (and worked for many years). When I switched to Proxy Group, item becomes "Unsupported" and generates an error:

Timeout "{$PING_TIMEOUT}" should be at least 50".

It looks like proxy can't substitute 2000 for the macro. 

If I switch such a host back to a "traditional" proxy, the item became enabled, and performs ICMP pings again.

fragments of my template (json export):

...
                "items": [
                    {
                        "uuid": "6ea092210ed4470c8acc15b3ec49e11c",
                        "name": "Ping",
                        "type": "SIMPLE",
                        "key": "icmpping[,4,25,,{$PING_TIMEOUT}]",
                        "delay": "90s",
                        "history": "10d",
                        "trends": "730d",
                        "description": "Ping",
                        "tags": [
                            {
                                "tag": "Application",
                                "value": "Ping Statistics"
                            }
                        ],
                    },
....
                "macros": [
                    {
                        "macro": "{$PING_TIMEOUT}",
                        "value": "2000"
                    },

The same problem is with active agent checks (described here ZBX-25283) but here I deliberately limit the bug report report to simple checks, to show, that it is not a problem on the agent's side, because it occurs even in the agentless setup (only pinging proxy).

ver 7.0.3 (zabbix_server and all zabbix_proxy)

Steps to reproduce:

1. create template (i.e. "generic_ping") with simple check, with macro in parameters
2. create next template (i.e. "linux") and add "generic_ping" to this template
3. create host, and attach "linux" template
4. create "traditional" proxy and Proxy Group
5. switch between proxies

Result:
**

error, only when using Proxy Group

Expected:

Macros should be substituted by any proxy type.