I have a Boston Acoustics C210 enclosed sub which runs 2 10" subs at 2 ohm. I just got - SONY XM-1S SLIM SERIES 900 WATT MONOBLOCK AMPLIFIER. The specs are:

900W Max Power
290W RMS into 4 ohms
40Hz Low Boost Switch
15Hz Subsonic Filter
Perfect for pick-up trucks & compact vehicles
Active Thermal Control
Line Level Thru-put
Line & Speaker level inputs
CEA-2006 Power Compliant
Max Power (Watts): 900W
Ad Hoc Power into 4 ohms, THD%: 1 x 290, 1
Ad Hoc Power into 2 ohms, THD%: 1 x 500, 1
Bridged into 4 ohms, THD%: N/A
Signal to noise ratio (dB): 90dB
Frequency Response (Hz): 5-300Hz
Input Level Range (V) Line level input: 0.3 - 6
Current Drain at rated output (A): 30
Width (inch): 8-7/9
Height (inch): 1-5/7
Depth (inch): 7-5/7
Weight (Approximate): 5.07lb

When I hooked it up one of the speakers in the enclosure isn't playing for some reason? Any idea what is going on? I need help pretty bad... I'm a newb at this stuff and tried to replace the Sony Amp (XM-D400P5) I had in there that the local stereo store installed for me. I thought I did everything the same (as far as hooking it up), but only one of the speakers in the enclosure is working.