RepairPal Certified shops can diagnose and repair your 2007 Volvo XC70. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.
Antenna connection issue, radio head unit issue or wiring. This will need a hands-on inspection to be sure. You can try bringing it to a place that installs stereos. Sometimes those guys can figure this kind of issue out really easily.
Alex