Citroen C5 radio system not working

Is there another fuse possibly engine bay to check

You checked fuse F8 in fuse box C ?

Fuse box under dashboard (Box A)
Citroen C5 mk2 - bezpieczniki - tablica rozdzielcza - skrzynka A
Citroen C5 mk2 – fuse box- under dashboard – box A
Symbol Ampere rating [A] Function
G29 — Not used
G30 5 Heated rear view mirrors
G31 5 Rain and brightness senso
G32 5 Seat belt not fastened warning lamps
G33 5 Electrochrome rear view mirrors
G34 20 Sun roof
G35 5 Passenger door lighting – Passenger rear view mirror adjustment
G36 30 Electric tailgate (tourer)
G37 25 Heated front seatsprzednie podgrzewane
G38 25 Driver’s electric seat
G39 40 Passenger’s electric seat – HIFI amplifi er
G40 3 Trailer relay unit supply
Dashboard fuses (Box B)
Symbol Ampere rating [A] Function
G36 15 6 speed automatic gearbox
5 4 speed automatic gearbox
G37 10 Daytime-running lamps – Diagnostic socket
G38 3 ESP
G39 10 Hydraulic suspension
G40 3 STOP switch
Dashboard fuses (Box C)
Citroen C5 mk2 - bezpieczniki - tablica rozdzielcza - skrzynka C
Citroen C5 mk2 – fuse box – (Box C)
Symbol Apmere rating [A] Functions
F1 15 Rear screen wiper (Tourer)
F2 30 Locking and deadlocking relay
F3 5 Airbags
F4 10 Automatic gearbox – Additional heater unit (Diesel) – Electrochrome rear view mirrors
F5 30 Front window – Sun roof – Passenger door lighting – Passenger rear view mirror adjustment
F6 30 Rear window
F7 5 Vanity mirror lighting – Glove box lighting – Interior lamps
F8 20 Radio – CD changer – Controls at the steering wheel – Display – Tyre defl ation detection
F9 30 Cigar-lighter – Front 12V socket
F10 15 Alarm – Controls on the steering wheel, signalling and screen wipe control
F11 15 Low current anti-theft switch
F12 15 Driver’s electric seat – Instrument panel – Seat belt not fastened warning lamps – Air conditioning controls
F13 5 Engine relay unit – Hydraulic suspension pump cut-off relay – Airbag ECU supply
F14 15 Rain and brightness sensor – Parking assistance – Passenger’s electric seat – Trailer relay unit – HIFI amplifi er ECU – Handsfree kit – Lane Departure Warning System
F15 30 Locking and deadlocking relay
F17 40 Heated rear screen – Exterior heated rear view mirrors
FSH SHUNT CUSTOMER PARK SHUNT
Fuse box in engine compartment
Citroen C5 mk2 - bezpieczniki - komora silnika
Citroen C5 mk2 – fuse box – in engine compartment
To access the fusebox in the engine compartment, undo each screw a 1/4 turn.

Symbol Ampere rating [A] Function
F1 20 Engine control unit
F2 15 Horn
F3 10 Screen wash pump
F4 10 Headlamp wash pump
F5 15 Starter
F6 10 Air fl ow meter – Directional headlamps – Diagnostic socket
F7 10 Automatic gearbox lever lock – Power steering
F8 25 Starter
F9 10 Clutch switch – STOP switch
F10 30 Starter
F11 40 Air conditioning blower
F12 30 Wipers
F13 40 BSI supply (ignition on)
F14 30 —
F15 10 Right-hand main beam
F16 10 Left-hand main beam
F17 15 Right-hand dipped beam
F18 15 Left-hand dipped beam
F19 15 Starter
F20 10 Starter
F21 5 Starter
Fuses on the battery (all engines except V6 HDI)
To access the fusebox located on the battery, detach and remove the cover.

Symbol Ampere rating [A] Function
F6 25 Rear 12V socket (max power: 100W)
F7 15 Foglamps
F8 20 Additional burner (Diesel)
F9 30 Electric parking brake

Have checked fuse in glove box that's ok. Have took out the radio and can't see anything wrong. I've just bought the car second hand and the dealer said it keeps blowing a fuse about every 6 months but the fuse is ok. Could it be something to do with the tow bar?

Have a read at this , might help

https://asacannes.com/en/comment-allumer-la-radio-sur-citroen-c5/