4-octet bitfield. Bit 0-30 = BIS_index[1-31]
0x00000000: 0b0 = Do not synchronize to BIS_index[x]
0xxxxxxxxx: 0b1 = Synchronize to BIS_index[x]
0xFFFFFFFF: means No preference if used in BroadcastAudioScanControlPoint,
Failed to sync if used in ReceiveState.
Broadcast Receive State characteristic as defined in
Broadcast Audio Scan Service spec v1.0 Section 3.2.
The Broadcast Receive State characteristic is used by the server to expose
information about a Broadcast Source. If the server has not written a
Source_ID value to the Broadcast Receive State characteristic, the Broadcast
Recieve State characteristic value shall be empty.
Trait for objects that represent a Broadcast Audio Scan Control Point
characteristic. When written by a client, the Broadcast Audio Scan Control
Point characteristic is defined as an 8-bit enumerated value, known as the
opcode, followed by zero or more parameter octets. The opcode represents the
operation that would be performed in the Broadcast Audio Scan Service
server. See BASS spec v1.0 Section 3.1 for details.