1999 Toyota Tacoma

I need help!!! I have a 1999 Toyota Tacoma manual shift and when driving with the air conditioning on my truck makes an odd noise. The noise is very sporatic but seems to happen most at about 50MPH and 70MPH. I am going to try and type out the sound…“Chht” It is quick and only happens once at a time. The power of the engine drops when it happens as though it may cut out. But it is very quick. Any thoughts??

I’m not sure on how to diagnose an intermittent with the AC system like that but wonder whether your AC compressor is locking up mechanically and that noise you’re hearing is the belt slipping. I do know that makes a weird noise (it did on my Tacoma).
Have you had the AC serviced recently?