Although the router only indicated that 100 Mbit concerns instead of 200Mbit, but for the music it was irrelevant. At least 100 Mbit it appeared in the test attempts to deliver.
Now comes the "but". The first set we have already exchanged after one year as an adapter has given up the ghost. LED failed to materialize and it was no longer possible to locate. Could be an isolated incident, so ordered the set again, because Amazon has reimbursed the complete set without problems. Thanks Amazon.
Since 1 exchange are now exactly two years and 2 weeks rum. Well, and again gave an adapter on the mind. Unfortunately Amazon refunded for two weeks not play the instrument. We do not want to re-take the risk anyway and switch to another manufacturer.