loud hum from power amp.


recently I upgraded my Mono power amp to a high power mono power amp. After connection, I noticed loud hum coming from my speakers. After reconnecting the system back to my old Power amps. the hum disappeared.

Can anyone pls tell me whether the problem originated from the new power amps? What can i do to address the problem?
kctan
lift the ground on the amp by using a 3 prong to a 2 prong adapter plug. Any hardware store has them. If the hum goes away and I am sure it will, a search here on ground loop has valuable info. Good Luck.