UARTE1 at 921600 baud rate doesn't receive more than 5 bytes if CONFIG_LOG is enabled.

Question

I am using the nrf5340 audio example project. The main problem is that I can not receive more than 5 bytes on UARTE1 at 921600 if logging is enabled. There is no event if I try to send more than 5 bytes of data. I guess that log module somehow crashes. If I disable the CONFIG_LOG macro from the .conf file everything starts working fine. But at a 115200 baud rate, UARTE1 receiving works fine while receiving big amounts of data, even if logging is enabled.

This is my device tree configuration:

/*
 * Copyright (c) 2020-2022 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#include "audio_gateway_nrf5340_cpuapp_common-pinctrl.dtsi"

/ {
	chosen {
		zephyr,console = &uart0;
		zephyr,shell-uart = &uart0;
		zephyr,uart-mcumgr = &uart0;
		zephyr,bt-mon-uart = &uart0;
		zephyr,bt-c2h-uart = &uart0;
		zephyr,bt-hci-rpmsg-ipc = &ipc0;
	};

	gpio_fwd: nrf-gpio-forwarder {
		compatible = "nordic,nrf-gpio-forwarder";
		status = "okay";
		uart {
			gpios = <&gpio1 9 0>, <&gpio1 8 0>, <&gpio1 11 0>, <&gpio1 10 0>;
		};
	};
};

&adc {
	status = "okay";
};

&gpiote {
	status = "okay";
};

&gpio0 {
	status = "okay";
};

&gpio1 {
	status = "okay";
};


&uart0 {
	status = "okay";
	current-speed = <115200>;
	pinctrl-0 = <&uart0_default>;
	pinctrl-1 = <&uart0_sleep>;
	pinctrl-names = "default", "sleep";
};

&uart1 {
	status = "okay";
	compatible = "nordic,nrf-uarte";
	current-speed = <921600>;
	pinctrl-0 = <&uart1_default>;
	pinctrl-1 = <&uart1_sleep>;
	pinctrl-names = "default", "sleep";
};

&pwm0 {
	status = "okay";
};

&timer0 {
	status = "okay";
};

&timer1 {
	status = "okay";
};

&timer2 {
	status = "okay";
};

&flash0 {
	partitions {
		compatible = "fixed-partitions";
		#address-cells = <1>;
		#size-cells = <1>;

		boot_partition: partition@0 {
			label = "mcuboot";
			reg = <0x00000000 0x00010000>;
		};
		slot0_partition: partition@10000 {
			label = "image-0";
		};
		slot0_ns_partition: partition@50000 {
			label = "image-0-nonsecure";
		};
		slot1_partition: partition@80000 {
			label = "image-1";
		};
		slot1_ns_partition: partition@c0000 {
			label = "image-1-nonsecure";
		};
		scratch_partition: partition@f0000 {
			label = "image-scratch";
			reg = <0x000f0000 0xa000>;
		};
		storage_partition: partition@fa000 {
			label = "storage";
			reg = <0x000fa000 0x00006000>;
		};
	};
};

/ {
	reserved-memory {
		#address-cells = <1>;
		#size-cells = <1>;
		ranges;

		sram0_image: image@20000000 {
			/* Zephyr image(s) memory */
		};

		sram0_s: image_s@20000000 {
			/* Secure image memory */
		};

		sram0_ns: image_ns@20040000 {
			/* Non-Secure image memory */
		};
	};
};

/* Include partition configuration file */
#include "audio_gateway_nrf5340_cpuapp_partition_conf.dts"
// #include "audio_gateway_nrf5340_shared.dts"

This is my pins configuration:

/*
 * Copyright (c) 2022 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */

&pinctrl {
	uart0_default: uart0_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 20)>,
				<NRF_PSEL(UART_RTS, 0, 19)>;
		};
		group2 {
			psels = <NRF_PSEL(UART_RX, 0, 22)>,
				<NRF_PSEL(UART_CTS, 0, 21)>;
			bias-pull-up;
		};
	};

	uart0_sleep: uart0_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 0, 20)>,
				<NRF_PSEL(UART_RX, 0, 22)>,
				<NRF_PSEL(UART_RTS, 0, 19)>,
				<NRF_PSEL(UART_CTS, 0, 21)>;
			low-power-enable;
		};
	};

	uart1_default: uart1_default {
		group1 {
			psels = <NRF_PSEL(UART_TX, 1, 14)>;
		};
		group2 {
			psels = <NRF_PSEL(UART_RX, 1, 15)>;
			bias-pull-up;
		};
	};

	uart1_sleep: uart1_sleep {
		group1 {
			psels = <NRF_PSEL(UART_TX, 1, 14)>,
				<NRF_PSEL(UART_RX, 1, 15)>;
			low-power-enable;
		};
	};
};

I thought that the reason could be easyDMA but couldn't find enough information about it. What do you think can be the cause of this trouble?