Oval 9 Sp. Cables Making Arcam 10 int. clip?

I just purchased a pair of AP Oval 9's (12') with T1Spades. I hooked these large cables up to my Arcam 10 Intergrated which is a 100 W/channel amp. I am only using one pair of speaker cables. My single pair of Paradigm 100's are rated at 8 ohms.

After 20 minutes of playing at medium volume, the amp appears to be clipping. No distortion ever heard -- just a loud pop every once in awhile and sometimes it cuts out the sound completely for 2 or 3 seconds. What is happening here?

Simply putting large cables on one set of speakers shouldn't increase current being supplied by the amp. The resistance is set by the speaker, not the cable, isn't it?

Any ideas would be appreciated.

John