Hi @cstofko
You mentioned that the corded phone is having issues,
Had you tried this?
Ask someone to make a call to your telephone number, pick up on the defective set.
you will not be able to hear, but try speaking on it. Does the remote caller hear your voice?
If the remote caller does not hear you, consider getting another cable to change from the base station to handset.
see if it work.
or test with another handset.
else dismantle the handset and check on the internal speaker if it is working.