lost sound from external speakers after changing thermal paste

Hello

sorry for my English - I'm from Ukraine and using google translate.

after replacing the thermal paste is missing the sound from external speakers

the sound from the headphones still work

I did reset the PRAM and SMC but it did not help

during replacement of thermal paste, I just disconnected the right speaker and subwoofer, the left speaker, do not disconnect

After assembly, the sound was gone - he's still there in the settings, but there is no sound

please tell me that I could hurt in the process of dismantling

and depends on whether the failure such as the right speaker to work both speakers?