Following up on K0SPN's comments as he didn't take into account the SignaLink USB device.
Find the computer sound level that kicks the vox circuit ON in the SignaLink USB device then raise it another 10% to make sure slight variations from the computer does not allow the radio to drop out of transmit. Once at that point leave the computer sound level alone.
Set the IC-7000 to 100% power level. Use the TX knob on the SignaLink USB to adjust your output power level. It has been reported that the back panel connector (small DIN) can have high sensitivity. This issue is addressed on the Tigertronics site by using a resistor in the jumper block inside the SignaLink USB. I forget the value I used, but seem to recall it was a little higher than commonly used/recommended.
I monitor the power out with the LED meter on the LDG AT-100ProII Autotuner. I typically run an indicated 10-12.5 watts and have only gone to about 25 watts when my signal reports is near -24. With that setup I never have any ALC. ALC in the 7000 is not turned off. You setup so you can't get to that point.
I am not sure if the radio indicates ALC when the SWR is high and the power is being reduce because of that. That's the only case that I can think of that might give ALC with 100% radio power setting and audio level that keep the RF output below 25 watts.
The road goes on forever and the party never ends...