Amplifier humming

Hi Gnana- Some transformers hum. It can be caused by a variety of things, including some slight DC on the line, or by other aspects of "dirty" power resulting from things like dimmer switches, fluorescent lights, or certain kinds of motors on the same phase of the power distribution box as your amp. It can also be a mechanical vibration type hum which can sometimes be eliminated or reduced by tightening (but not over-tightening) the transformer hold down bolts or nuts. It will not cause any harm to your components and if your speakers are dead silent, should not have any effect on sound quality.

If you bought an amp new, noticeable transformer hum may be part of warranty service. However, a SLIGHT HUM may be in all their amps that are using that type of transformer.

Swampwalker has provided a possible fix. In the case of DC on your power line, there are units that filter the DC such as the Emotiva CMX-2.
https://emotiva.com/products/accessories/cmx-2

I use a P.S. Audio Humbuster III...although no longer made you can still find them on Ebay or someplace and they work GREAT to solve that exact issue.

The AW250R stereo amp for India may be 230V, please confirm this as the power strip/conditioner needs to support that rating.