OK, so the rules in question are on p. 225 in the BBB.

To intercept a wireless signal is an electronic warfare + Sniffer test (3) test. Nothing That I can find in any book effects that threshold. This is boring enough under the normal rules, but if you are using the "Attributes matter" rules tweak in Unwired, then you only ever need a rating 3 sniffer program. Any less, and it cannot function. Any more never matters.

I'm thinking of correcting this by making the threshold based on a program the defending commlink is running. This would represent scripts that change the frequency used on a semi-random basis, and puts out chaff to disguise signal as noise.

I have three sub-options to that. The first and second are using existing programs. Firewall might work here, as this is a type of defence. This would mean every commlink did this, though, and that isn't quite right. Normal users don't really need this function. The second option is Encryption. Any encrypted signals would use the rating of the encryption for the threshold. The latter is to make an entirely new program.

Another option would be to have the owner of the commlink that wants to make it harder make an electronic warfare + logic check (complex action), adding their hits to the threshold. At any point they may make this check again, replacing their previous result, and forcing anyone intercepting their traffic to recheck.

Any other ideas?

Simply add the Stealth Programm to the Rating and its okay. If it is envrypted, he has to decrypt it first. If he won't decrypt it, the signal goes SIZZLE instead of wealthy informations about the new Renraku Firewall Prototype

Sniffer is also incredibly useful for tapping wired communications and tapping communications passing through any node. It's Hacking + Sniffer with hits equal to the Threshold for anyone trying to find the tap.

Consider this before making a houserule.

Why get the program when you can get the Radio Signal Scanner RFID Sensor for 150 ? I mean honestly, it's cheaper and just as easy to use. Get it skinlinked for another 100 and wear it like a wristwatch. It can feed the info directly into your commlink. No need to load up your commlink with another program.

Because you can't tap a node across the Pacific with a short range radio signal scanner. If you're digging for dirt on a contact bugging his apartment's likely routing nodes or even bugging his trodes (probably doesn't ever Analyze those!) would provide you with a wealth of info without having to be physically close to him.

I hadn't even Thought about the stealth program, but now that you mention it, it's perfect.

"To intercept a wireless signal is an electronic warfare + Sniffer test (Target's stealth) test"

That seems to work.