Carver M 1.5 Ocillation when connect with Denon AR 989

I have M1.5 which Only ocillates with Denon reciever. It is working perfect with any other brand seperates. This unit has M1.5 signature low humm at no input connection. Humm goes away with my Teak CD player directly connecto it. But humm(oscillation) gets really loud with my new Denon reciever(pre out). I have no problem with my Caver M1.0t or TFM-15 working with my Denon reciever.I'd like to hear from the member who has same experiences.
Thanks in advance

Sounds like a grounding problem. The TEAC apparently is providing a good ground through the shields on the ICs, which makes the hum go away. No such luck with the Denon. Have you tried hooking the grounding post (chassis) from the Denon to the M-1.5? BTW, is that an M-1.5t or a PM-1.5?

It is M1.5.

Do you have cable tv attached to the Denon? That is a HUGE source of ground loop hum.

I shure do have my Comcast attach to it. I never thought about that. I will take your advice tonight.

I just disconnect every thing but a cd player Denon reciever, M1.5 and apair of speakers. I am not hearing any humm. I just need to reconnect one by one to see which one is culprit here.

Thank you

I kind found source of problem. I found my projector or Denon reciever is causing problem. As soon as ground prong of AC plug of projector touches AC outlet, my M1.5 humms not M1.0t nor TFM 15. My NEC projector is connected to component output of Denon reciever. I am not sure which one is cuase of problem at this point.

It was my NEC projector injecting humms into Denon receiver. I disconnected Projector and problem solved until I need to watch movie. Thank you everyone.