Had the same problem. Found some of the tape from the new battery was keeping the loudspeaker from connecting to the motherboard. Ended up reinstalling the new battery higher in the battery compartment. After the battery was reinstalled, I removed the battery from the midframe and pushed it against the connector with the power on and music playing to test if I was getting sound. Once I was sure sound was playing, I reinstalled the midframe while pushing hard on the area with the speaker, and installed the screws closest to the speaker first. Works now.