For whatever reason there is always a few like 2 or 3 people out of however many users on this forum who have this issue. It's very frustrating I'm sure because nobody else has this problem regardless of what kind of system they have. For 99.5% of us we install Biab, enter some chords, pick a style and hit Play and everything is good.

You mentioned ASIO with your Delta. That random crackling is a classic sign the buffers are too low. Just keep raising them until the crackling stops. It's also possible their old ASIO driver isn't that good, who knows? You can try downloading the freeware ASIO4ALL and see if that helps.

One point unrelated to this. You said you're using MS Security Essentials. Bad idea because it's simply not that good. One very big reason to upgrade to Win 10 is the new Windows Defender is much better and no it can't be added to an old Win 7 system. I'm not going into all that here, for a whole variety of reasons everybody should be on Win 10.

Bob

Biab/RB latest build, Win 11 Pro, Ryzen 5 5600 G, 512 Gig SSD, 16 Gigs Ram, Steinberg UR22 MkII, Roland Sonic Cell, Kurzweil PC3, Hammond SK1, Korg PA3XPro, Garritan JABB, Hypercanvas, Sampletank 3, more.