Getting robotic echo when using "high quality stretching" on the Change Tempo effect.

Hi. I’ve been trying to use the “Use high quality stretching (slow)” option of the Change Tempo effect when lowering the tempo, because the “normal quality” isn’t good enough for my needs, but rather than getting better results, I’ve been getting very inferior, completely useless results. The “high quality” version has an extremely strong robotic echo sounding-like noise to it. This happens even if I only try to reduce the tempo by 4%.

So far I’ve tried restarting and upgrading to the latest version of Audacity, and neither thing has helped. I’m using Audacity 3.2.4, but also had this problem when I was using Audacity 2.3.2. I’m using Windows 10 x64.

Anyone have any idea what I should try to troubleshoot this? This can’t possibly be normal behavior, right?

Thanks for any suggestions or tips!

Here’s a sample followed by the same sample with its tempo reduced by 16%, for your reference.

That’s how speech sounds with “high quality” stretching in Audacity.

Okay. Glad to know it’s not just some kind of problem with my setup. Thanks!