First of all, check your Flash Player version.
Make sure that you have latest available version suitable for your operation system.

In Chrome, check plugins: chrome://plugins
If you have PepperFlash enabled, you need either

1. Turn off PepperFlash and enable lash\NPSWF32_11_5_502_110.dll
or
2. Set to false in flashphoner.properties file and clean the browser cache.

Note,

Chrome PepperFlash has this latency bug in Chrome 23.
So, if you disable enchanced mic, you disable Echo cancellation.
If you enable enchanced mic you have latency in chrome browser.
We hope the issue will be fixed in latest versions of Chrome.