Keep in mind that you can only use the coin size that the hopper escalator is designed for. If that's a quarter escalator, only quarters may be used -- not "quarter-sized" tokens, not nickels, nothing else, or it will jam.
Sound volume is controlled by a small blue potentiometer wheel on the edge of the MPU board. Although there could be other reasons you're not getting sound, the easiest thing to start with is to just rotate the knob back and forth a number of times to help clean off any oxidation within the device, and then leave it near the middle to ensure that you have it dialed to a point where you should hear sounds. If that doesn't do it, post back and we can get into some more troubleshooting. I have added an arrow to your picture to show you where that volume control is.
There is a manual available in the downloads section, but you must be a contributing member to be able to access it. Be aware that the manual is old and isn't comprehensive, and will not necessarily have troubleshooting steps for every potential issue. Our members here have years of experience and will help you get your machine up and running 100%.
That said, looking at your previous posts it looks like you've gotten a lot of help with getting various machines up and running through the use of this website. I'd really encourage you to consider becoming a contributing member. When you do, you'll have access to lots of information in the downloads section, you'll have a larger inbox for your private messages, and you'll be helping to support and fund the web hosting that keeps this site alive to help folks with their machines. NLG offers an
ongoing subscription option where you can pay a nominal monthly fee for these benefits, or you can choose to
make a one-time donation which will get you "contributing member" status for an amount of time determined by Joey, the owner of the site. Every little bit helps. Thanks for your consideration.