radio is real low and static. on 2008 Kia Spectra

Cd player works great, but radio plays with volume low and static.Tore out the radio, and no visible issues, even antenna is not loose. No burnt fuse. What could this be.

2 answers
Do you have something to use as a 'test' antenna?
Defective radio receiver most likely! Factory stereo or has it been replaced?