Got a refurb TiVo Bolt 500 GB during Black Friday sales. Been working fine until today. Was watching live TV, when picture on TV froze. Tried changing tuner, but TiVo would not respond to commands. Tried changing channels on same tuner, also no response. Turned off TV. Turned TV back on; TV says no signal. TiVo light stayed on this whole time. Tried power-cycling TiVo by unplugging power cord. Now no lights appear on TiVo and no signal appears on TV. I can hear what I think is fan spinning now. Please help. Thanks.