I am paid X amount on the books but more in cash and i think im going to be fired soon?

I have worked for my employer for well over 15 years. There was a dispute in the company between owners. The majority owner the one that runs the day to day operations thinks that i gave information to the other owner to help him in his legal battle. Since he believes this in his head things have gotten really bad for me at work. All my authority has been taken away. (manager id card, keys, managing my staff) The assistant manager is now running everything. I am still working here but i feel that my days are numbered. I am paid a salary of X amount (as a manager) but i am paid in cash for more money. He has just lowered my salary on the books without saying anything to me about it. (My employer pays all employees cash. What he does is he puts all regular employees on the books for there hourly amount but not over 40hrs. 95% of employees work well over 40hrs. When its pay time we receive a check and stub with a envelope full of cash. We have to sign our pay check and give it back to him and then we are given the stub and the envelope of cash. Some employees ask him if they can only on the books for 20-25 hours so they can keep thieir state benefits welfare, state insurance ect..) He is still paying me in cash for my normal amount he just lowered my check. I believe he is doing this to lessen my unemployment. I already know that since i am paid in cash for more than my check says that i will only receive unemployment based on my check amount.(my employer gave me a raise awhile back and what he told me was he was going to pay my taxes for me. Example: i get paid the full amount that my check says before taxes) Also i am paid salary based on 50hr/wk but if i work less i get deducted. I work in Pennsylvania.