i have a hum on 1 channel i have traced the source of it and it would appear its the cartridge which is audio technica 120.i proved this by re installing an old linn k5 now no hum.my question is stick with hum.use the linn or buy new cartridge or wait for rega p 3 as my turntable is now 30 years old rega planner 2.also if its cartridge change which one.i read some cartridges do hum find that hard to believe.