Sorry, I should have said, see this post: https://forum.audacityteam.org/t/mic-to-headphone-latency/26412/9
I know that the topic is different, but that specific post is probably relevant.
If it still does not make sense or you don’t see the relevance, please describe in detail what you have plugged into where, what settings you have in the Device Toolbar and precisely how your mixer is set up.
Basically the Alesis multimix does not seem to be very good for overdub recording with Audacity, but if I know exactly how you have it set up I may be able to help you to get it better than now.