The idler pulley for the AC compressor belt can fail causing a growling type noise. The idler pulley will have to be replaced to stop the noise.
Car Problem Reports
Honda Civic Si Replace AC Idler Pulley to Stop Growling Noise
Honda Civic Si Problem
Average Mileage: 101,601 mi (65,000 mi - 138,203 mi)
Visitor, 1999 Honda Civic Si, 138,203 mi
my ac is a sqeeling noise i put belt dressing on were the sqeeling was coming from and it went away but came back 2 min later compressor cost 300,00