Hello Thomas, not an expert here but i use to have those 3 devices together in my shack.
What i can say is (some already told)
Those icom rigs are well known for alc overshoot.
So, use a good quality alc cable and calibrate alc level on the linear as stated in the manual. Most modern systems dont need it, but as told by the technician, use it.
When transmitting set the audio chain in the 7610, including comp and mic gain, eq, try Hand mic first, so never reach near the end of alc scale (red line), be conservative.
Super important: There is a semi hidden menu in the radio that is a tx gain compensation (i guess). Access via quick menu, ?Never touch that for nothing. My level was 47. How to unorthodoxy know its wrong or not: record a voice message, play it back transmitting and monitor with headphones. If there is a slight distortion, go back a notch. Record again, test.
Reflected power is a devil sometimes. If using a balanced antena fed with coax, put an adequate choke at the feed point. If using ladder line, choke the transition to coax outside the shack.
Use good ground strips, bus and conductor to rods.
Maybe you already know all of this info but those are my 5 cents :)
PS: If able try to put a PEP meter in line like a smorf or a lp100a, or a dc powered bird 43.
While in RTTY set your pep till reach 1000 watts then go SSB. Dont try to get 1kw using ssb and a wattmeter. Thats ?a SS amp killer combo.
Let us know how it went please.
73,
Philip
CE4PS
Philip Smith