Just to expand on my last post
The tac board seems ok but itās the carpet padding that is bad and making me go crazy as I have carpet bumps
I canāt just get to the padding
I guess I have to get a knife and fold the carpet back
I canāt do anything
I had a simpler problem in a living room and bedroom. I called a carpet installer and he charged me about $100 to fix it. There was two problems. In the living room, some idiot ran an an electric cord under the carpet. In the bedroom, the original installer use two different pads and one worn down faster or it was a thinner pad. Anyway the carpet guy fixed it in about 30 mins.
BTW, a common problem causing bumps in carpet is it needs stretching. Older carpet often have to be re-stretched. Hope this is of some help.