I think it likely that manufacturers will look at distributed mode technology again.
I own a pair of NXT speakers. They are picture frames and have a pair of prints in them. They worked really well for what I bought them for and had sound much better than you'd expect from flat speakers.
My S3 has been fine with both GiffGaff* and 3 SIMs since the upgrade. If you've not already tried, try toggling airplane mode, otherwise you'll probably need to do a factory reset.
* GiffGaff requires you to manually enter the APN settings.