If you’ve got Siemens hearing aids, someone up there loves you, and as a consequence you can now stream music and patch calls directly into said devices.
The Siemens miniTek is a small, ultraportable black box that will pick up audio from Bluetooth devices and stream it to your hearing aid. It also works with T-coil and e2e wireless systems, and if you want to use something with cables, a 3.5mm jack will handle your business.
Battery lasts for 5 hours if you’re listening to music, and will make it a few days when using the miniTek as a remote for answering calls. Pricing is available from your audio specialist, so don’t waste any time and go bug him about it.