Endless stream of "Suspicious packet count xxx when bytes xxx for flow xxxx" followed by "Flow details for excess packet count " in Console I have a 2018 MacBook Air Retina.
Fresh reinstall of macOS Catalina (10.15.5). Nothing installed except apple numbers, pages and google chrome.
After a few hours, after noticing that on idle the fans are spinning at maximim, I opened Console.
In &quot;Errors&quot; I  have an endless stream of
&quot;error 09:41:36.901853+0300 symptomsd Suspicious packet count 121 when bytes 968 for flow 7434&quot;
and
&quot;error 09:45:08.399365+0300 symptomsd Flow details for excess packet count &quot;
If I check Network Utility I see that the packages are sent via the Ethernet network interface.
And this goes on forever, and my macbook is getting really hot and slow, to the point I can't use it anymore.
This continues even after I turn off wifi.
I did SMC and NVRAM resets, nothing.
In my experience, the symptomsd &quot;Suspicious packet count&quot; is caused by a problem with the Apple Wallet. Go to System Preferences -&gt; Wallet &amp; Apple Pay (on Catalina, might be different on other versions of macOS) and verify that all your cards are still good.
You might also see errors like &quot;SEID Changed&quot; or &quot;Hardware has changed&quot; or complaints from nfcd if you have restored a wallet backup to a different computer (or a repaired computer that had its T2 chip replaced).