SunSDR2 EESDR2, EESDR3 CW delay solution
For Windows PCs, sound latency is often very high in real-time audio processing applications due to integrated motherboard sound cards. Typically, an expensive external or (where possible) an internal professional ASIO-capable sound card is required.
Another solution, though far from perfect, is using ASIO4ALL, which reduces delay to some extent. However, since most PCs are equipped with Realtek onboard sound chips, there is a better way.
The solution is surprisingly simple: install a native Realtek ASIO driver. For some reason, the manufacturer does not bundle this driver with standard updates, so it must be installed manually. I have tested it, and it can achieve latency values comparable to professional external ASIO interfaces. This also works perfectly on laptops, as most of them use Realtek hardware.
I discovered the ASIO driver within a Dell laptop driver package, but it isn't installed automatically there either. The trick is that the main installer doesn't include it; you must unzip the package and locate the "ASIO" directory. Inside, you will find the factory Realtek ASIO installer, which needs to be run separately. Once installed, a new audio device named "Realtek ASIO" will appear in your system.
This device should be selected in your software (e.g., ExpertSDR). Using an ASIO driver not only fixes latency but also reduces CPU load. This method works with other SDR or audio processing software as well. In ExpertSDR Remote mode, the latency is prohibitively high without an ASIO driver, making its use highly recommended.
I have included the installation kit as a separate download. Good luck!