Best Buy is waiting for a wave of shoppers to replace old devices and upgrade to new, higher-tech ones after an approximately two-year sales slump.

Best Buy Co. cut its full-year guidance on sluggish demand for electronics and appliances, a sign of trouble for the retailer looking to pull off a turnaround.Though shoppers are responding to holiday promotions,

The retailer lowered revenue and earnings guidance for the year after shaky demand in the back half of the third quarter dented sales.

Best Buy trimmed its annual profit and sales forecasts on Tuesday, signaling a muted holiday shopping season amid sluggish demand for pricey electronics such as televisions and home theater systems. Its shares were down 3% before the bell as the company also reported a much bigger-than-expected drop in comparable sales in the third quarter.