Quote:
I think I have found the EMI issue. When the phone is using mobile Internet (over GSM) - the noise is very loud.
No problem with GSM calls or WiFi Internet.
Here in Australia i'm still getting some noise when I use a mobile wifi hotspot, unless my hotspot is in a different pocket, so i'm having some success there - so I might have my pocket wifi in right jacket pocket, the amp in my left jacket pocket and my phone in my right pants pocket or inside jacket pocket (which is higher up than the right jacket pocket).
In summer I might have a bit of a problem lol.
I use a seperate mobile wifi hotspot for streaming music often due to the cost of data on my main provider being so high. The 2nd provider is cheap but unreliable, and useless for voice calls, so i do need both.
So it might depend on what frequencies your mobile internet is using. On 900 (2G/3G) and 850mhtz (3G) the noise is quite loud, i can really hear it inside buildings and lifts. At 2100mhtz (3G) and 1800mhtz (4G) the noise is reduced, but still there. Again keeping any RF emitting devices away from the amp (by 5cm - that's 2 inches for you Americans) seems to be a solution.
I'll report back on what difference a shielded cable between the amp and the phone makes when it comes, but i think the noise could be generated by the amp itself, not it's cabling.
*edit* The reason why a lot of people have success with using wifi instead is because the wifi transmitter is much further away from the amp than your phone is. When I walk into my house still wearing my headphones these interference issues go away as I jump on the home wifi.