[ICOM] re:IC761 PSK Drive

[zl3kr]

I am wondering if anyone using and IC761 for PSK and connecting thru the 
ACC Jack has had any problems with insufficient drive.
Reading the Instruction Manual I note that it says for AFSK into the ACC
input that it requires 150Mv RMS to get full output.
I am not sure whether the newer PCI Sound Cards are capable of 
delivering that amount of drive, seeing as how they are designed to 
drive amplified speaker systems. I know of IC761 users who drive through 
the Mic jack and of course that would bring the Mic preamps into use, so
is apparently not a problem, I am unable to get more than 4 or 5 watts 
output with the RF Power control fully wound up.
I am trying to decide if I should build  a simple Opamp preamp and 
install it in the audio line for the ACC jack or if it maybe
my RealTek AC97 Sound card that could be defficient.
73  Alan ZL3KR