Hello, and sorry you're having problems. We are now connected on this website- which saves you money over having a Tech come to your home, and in many cases we can fix the problem you're having. In other cases, these things do require additional parts to fix. But I can help you with that as well.
How long have you owned the Pioneer for and when did the problem occur?
Generally the MCACC light blinking means there's a short sensed at the speaker output terminals (meaning either a speaker, or speaker wire is shorted). However it can be caused by several things.
Are you able to get any response at all from the setup menu, or change sources, etc. on the Pioneer?
Also how long have you owned it for and when did the problem occur?
Feel free to reply back if you need more help, or want to reply back with more details. It does not cost you anything more to reply back once you've rated. Please do rate me positively (at least 3 STARS) and I will continue with you until this is sorted. The positive rating ensures I am credited for my work.