AC
 

My AC has been acting up lately. There is usually a 3 second delay for it to come on, and than it seems like it is ALWAYS on Low. Even if you have it on High, it still blows Low. Sometimes if you turn it off than on, or just keep turning the nob from high to low, it will blow High for a few minutes and than low again. Its blowing Ice cold, just not hard enough. Sometimes I can hear a clicking sound in the vent on the passenger side. I took it to a mechanic and he said I need to change my Motor Blower Control. He came up with this only after sitting in my car for 5 seconds, soI kinda want a second opinion.

I drive a Lexus RX300 1999

Do you think this will fix the problem or could it be something else?