All

I have now had an official repsone from the Tigertronics Support Team.
Intresting answer..

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Thank you for your email. Regarding your question about the SignaLink
USB, we have heard of this issue before with a few IC-706 units. The
problem is with the radio (not the SignaLink) and is caused by a lack
of isolation between the radio's Mic and Accy jacks. Normally the
ACCY Port is fully isolated from the mic jack and whatever you attach
there will not affect the Mic audio. However, on some 706 radios,
they seem to be lacking in isolation, and the ACCY Port loads down the
Mic circuitry which results in weak Mic audio until you turn up the
Mic gain.

You can most likely resolve this issue by adding some isolation inside
the SignaLink. This can easily be done by simply replacing the
SignaLink's "Mic" jumper wire that you installed in JP1 with a
standard
1/4 watt resistor (this will simply plug-in in place of the regular
jumper wire). We suggest starting with a 2.7K value and go up from
there until you find a value that adds enough isolation to let you
keep the Mic gain control set normally (try 2.7K, 4.7K, 10K, 18K, etc.
- standard value).

Note that you need to use a 1/4 watt size resistor (nothing larger or
you'll damage the JP1 socket). Also, during digital operation you may
need to turn up the software volume controls (or the SignaLink's TX
knob if you have the USB version) to offset the additional attenuation
from the resistor. Please let us know if you have any further
questions.
Thank you.

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